How to get max value in datatable column in vb net

How to get max value in datatable column in vb net. Rows (i). While dr. You can simplify your code by using the Field (Of T) method of the DataRow combined with the If operator, note that you shouldn't need a nullable cc if you don't want to use the value - something like this: toName = dt. Add(x) Next. Also note that I had to do a conversion on the value that I was summing because being a dynamically returned datatable didn't have the Feb 11, 2014 · I have a data table from which i am filtering data based on condition,but how to display specific columns only from the data table? Dim Dt As New DataTable. Compute("SUM([Total#])", Nothing) answered Dec 13, 2022 at 7:52. Dec 29, 2022 · First button to load the data table form SQL server (that you suggest/note you already have the data table). We intend to get the maximum value of all rows and all columns, except for Index and for null values. Common. It is an in-memory representation of structured data (like data read from a database). If dr. Dim q = From p In dt. max function works but . ExecuteReader() Dim value as Decimal If dr2. Field(Of Integer)("Yr"), Key . I have a relatively simple example table below, taken from a teaching website. 'in the first row, first column. Min functions are a declarative way of testing the 2 values against each other. Add columns into that data table object. Code int maxID = curriculmDataTable. End If. toString(); // (I didn't want to opt for boxing / unboxing) Correct me if I have misunderstood. cmd = con. Dim ColumnIndex as Integer = 0. DataRow. In this data --- the biggest Number is --- 6543 How to get it from vb. From this perspective, we calculate the maximum of maximums, that is, each record has a maximum value and we intend to find the maximum value of these maximums. string val = DataView[RowIndex][column index or column name in double quotes]. foreach (DataColumn dc in dataTable. str = "SELECT MAX(codigoprestamo) AS MAXIMUM FROM tblprestamosinteres". In VB (you didn't specify a language) something like: VB. Text = DTPerson. Mar 8, 2011 · I'm using vb. " We add 2 columns—each row will store a "Size" and "Team" value. Jun 1, 2023 · First example. NET 3. Let's say I have the following model. Item(23). Key select g. CurrentTimeCard = CInt(cmd. Dim iRow() As DataRow = ParticularSource. I already imported the data from the database into a DataTable in my software. g. I know one option is to loop through all records an copy data one by one in second DataTable. SELECT MAX(expression ) FROM tables. da. that's ok. Compute("SUM(Price)", $"[Vat_Per] = {RATE} AND [Sale_Free] = 'R'") Apr 18, 2016 · Dim Amounts As New DataTable 'Your code to load actual DataTable here Dim amountGrpByDates = From row In Amounts Group row By dateGroup = New With { Key . Count <> 0 will throw this exception: Object reference not set to an instance of an object. Rows ( DataRowCollection) as source, using the LINQ Select () method, you can transform the Rows[Column] content in the string format that you require. UnboxT`1. primaryKey(1) = table. Examples. Add(i, i + 10) Next A single LINQ query to calculate all occurences for every range even ordered descending: Used often in VB. net. Fill (dtStudents) Aug 3, 2014 · I am trying to get the sum of the column TotalAmount in my DataTable dt but I always get this error: Object reference not set to an instance of an object. Read() Then IF Not dr2. ToString. Rows(0). Dim amount As String = Datatable1. ToDouble(dr[dc. ExecuteReader. Columns. Add Rows with values into the object. Resolved: I had to alias the columns returned. I am using VB in Visual Studio 2012. Rows(0)(0) where ds is the name of your DataSet object. Here's a snippet using LINQ syntax: Dim maximumLengthForColumns = From c in dataTable. ToString()) ' read the first row, second column of the table'. if (dc. Field(Of Decimal)("Amount"))} Nov 9, 2015 · It returns just the single value of your query without creating an MySqlDataReader and all the infrastructure needed when you want to read more than one record one by one. next, we have a text box for user to enter the column name. Dim abc As Integer = Datagrid. Length > 0 then. 'cmd. Cast(Of DataGridViewCell)() If selectedCells. – marc_s. SumAmount = Group. Item("<ColumnName>") = Max. Sep 30, 2016 · Your query is currently trying to query number fields as strings, so if the datatable columns you're querying are indeed integers, then the correct syntax would be: Dim search() As DataRow = table. and this is how we declared the column of productid: ID INT NOT NULL IDENTITY(1,1) PRIMARY KEY, PRODUCTID AS 'PROD' + RIGHT('0'+Cast (id as VARCHAR(5) ),6)PERSISTED, Feb 18, 2014 · 1st question:-. Format to make columns but I need to know the max length of contents for each Column. IsDbNull(0) Value=dr2. AsEnumerable() where (string) row["username"] == "jack" group row by new {usernameKey = row["username"]} into g select new { jackHighestPrice = g. . For eg. tables(0). Gets an array of DataRow objects. Your column name contains non-alphanumeric characters, so it should be wrapped in square brackets or "`" (grave accent) quotes. Oct 9, 2020 · I'm using VB. Example. Its just to minimize confusion of what is what. For Each dtRow As DataRow In dt. Load '-----Load Name-----' Try Dim strcon As String = ConfigurationManager. Updated above comment. I tried to use the datatable compute function, but this will not be effective: Convert. net / winforms. Dec 17, 2015 · 1. Dim cmd2 As OleDbCommand = New OleDbCommand(str, conn) Dim dr As OleDbDataReader. Select method on the DataTable to get those rows: var maxRow = dt. RowStateFilter = "GroupingID = 0":DataGridView1. ColumnName] != DBNull. To get maximum value of a column that contains integer, I can use the following T-SQL comand. Fill(TrackingDt) Dim Rows() As DataRow = Dt. Value and you can just use zero explicitly. Twelve. Linq namespace) if you add these values to some collection: Dim numbers As New List(Of Integer) { 20, 30, 15, 25 }; Dim maxNumber As Integer = numbers. answered Oct 6, 2016 at 7:32. SelectedCells. Add("Id", GetType(Integer)) May 28, 2014 · Show activity on this post. Dim view As New DataView(OriginalDataSet) 'Put your original dataset into a dataview. Columns("MyColumn") table. The Math. Text = a + 1. Max(Function(innerList) innerList. Gets an array of all DataRow objects. I would like to know how do i obtain the maximum value of all the records in a datatable of a particular column? For example: Code: Dim da As New SqlDataAdapter . Format("ItemID = '{0}'", ParticularID)) ParticularSource is the name of my Dataset ParticularTable is the name of my Datatable ItemID is the field where I Searched on ParticularID is the value to be searched Aug 29, 2012 · Dim value=cmd2. Dec 4, 2023 · DataTable is an in-memory representation of structured data. Field(Of String)("Period") } Into Group Select New With { Key . Jun 28, 2012 · @Thinhbk "assign these node values to the first six columns of my datatable" Meaning : There are 3 Emp name and 3 Emp ID in XML which should be assigned to Employee_1,Employee_2,Employee_3,EmpID_1,EmpID_2,EmpID_3 of my datatable. vb. Rows) {. Expand table. Assembly: System. You could write something like this: SELECT * FROM MyTable WHERE uid IN (123, 456, 789) That's effectively what I want to do with a DataTable in VB. GetDecimal(0) End IF End If 3. Dim index As New List(Of String)(table. For Each col As DataColumn In DataTable1. 5 or later, LINQ is the answer, e. i += 1. Applicable = False. End of example. Access it just like you're doing with username (by column name):. Compute or Linq-To-DataSet: create an int column: curriculmDataTable. Same goes for the minimum: Oct 6, 2016 · To clear every column at beginning of the loop you have two options: loop all rows. Format("SUM({0})", col. For large amount of rows i prefer the second option. value1 hello. Field(Of Integer)("Mnth"), Key . Using cmd As New OleDbCommand(query, myconnection) Try. Field(Of String)("col2") Equals cell. net I want the max length in col1 5. We create a DataTable with the name "Players. Dec 22, 2012 · Saw some examples in c#, but couldn't translate those to vb. Net then you should follow these steps as mentioned below : Create Data table object. The sample determines the minimum and maximum values for the results by using the Aggregate and Group By clauses. So your statement should be: decTotalNumber = BusinessAnalytics. Any Then. Dim Row() As Data. CommandText = "select MAX(won) from field_copy_no". AgeGrade) . If we have days 1 to 5, day 5 is the one Mar 21, 2014 · How can i get the max value of the column with a lambda expression in vb net? thanks! Find the maximum value of a VB. Cells (0). view. Nov 8, 2013 · Try. Tables(ParticularTable). If row. When the GetTable function is invoked, it creates a new DataTable and adds 4 columns to it. Jun 27, 2009 · If you want to consider maxLength for each column of table with multi line cell value. Item("<ColumnName>") > Max Then. 'Update DataTable. – Apr 13, 2018 · With the above example, the total amount would be 9, 600. How can i achieve this using linq Dim DT as new datatable datatable. WriteLine Row. You want to find the max value from each inner list ; you can get it by first getting the maximum for each inner list and then the max of those maximums. Apr 30, 2013 · Welcome to StackOverflow: if you post code, XML or data samples, please highlight those lines in the text editor and click on the "code samples" button ( { } ) on the editor toolbar to nicely format and syntax highlight it. Add("Max", GetType(Int32)) For i = 0 To 90 Step 10 rangeTable. Text with the 2nd column of the 3rd row, then you can use : Dim searchedValue As String = Nothing. Add(New DataColumn("MyColumn")) Dim primaryKey(1) As DataColumn. PrimaryKey = primaryKey. Item(1) Actually you should rename datatable1 to dataset1 since a datatable is a possible member of a dataset. Sum(Function(x) x. Depending on the plenty of rows the two options have different performances. I saw this post: Query rows that the datatable field contain any item in the list Aug 28, 2013 · Use the Select method of the DataTable to locate a specific row and assign new values to the desired columns. We have several concepts of maximum here. Rows Try 'Show all 3 fields/columns Console. Join cell In selectedCells On row. For Each grp In query. Each DataColumn has a DataType property that determines the kind of data the DataColumn contains. ColumnName != "Index" && dr[dc. Oct 1, 2008 · Building upon the above, I wanted to get the best result in each group into a list of the same type as the original list: var bests = from x in origRecords group x by x. I tried with Select, DefaultView. I would like to know how do i obtain the maximum value of all the records in a datatable of a particular column? For example: Dim da As New SqlDataAdapter Dim dtStudents As New DataTable da. Nov 30, 2018 · What I want to do is select max step value. Info Columns are named with a string argument and a Type argument. HasRows Then. min keeps showing zero. value2 my name is. now this is working except i am not sure how to select specific columns, like i don't want Dec 5, 2023 · A summary. 5. Count label1. Values. 00 since Room 101 and Room 102 of day 3 is not included. So you need to read up on that to better understand what's To retrieve the maximum allowed length, simply scan through the DataColumns property of the supplied DataTable object and use the MaxLength property. 1 = f_amount. rs = cmd. There are 5000+ records and performance is a key factor. Jun 10, 2016 · My goal is to show the whole content of a DataTable into a RichTextBox so I thought about using String. Because data that is contained by the DataTable is typically Dim view As New DataView(OriginalDataSet) 'Put your original dataset into a dataview. To be able to use the primary key, you need to ensure that all values for the given column are unique. We call Rows. Apr 2, 2013 · 7. Value MsgBox (abcd) IF the column (0) load from accending then it will ofcourse get the largest when the user sorts the column or any column it simply gets the last rows cell (0) value. RowCount - 1 Dim abcd As Integer = Datagrid. Dim result = dt2. Max(x => x. Mnth = row. Dim query = From r In bookedorders Group By key = r. Select returns an IEnumerable (Of T) (and you are working with the DataRows of your DataTable so you get an IEnumerable (Of DataRow). Tables("Table1"). Add(row(keyColumnIndex)) Next. Dim totalCount As Double. Dim Description As String = "Hello World Modified". Dim newNumber As Integer. The problem is, when I execute the following code, it is giving me the number of rows rather than the 6 distinct values. Looks like you want get "ID" from first row in your DataTable without using For Each loop. Into totalForType = Sum(Convert. Jun 10, 2016 · how to find the maximum length of a column in a datatable using linq in vb. Value Catch Ex As Exception End Try Next Jan 1, 2021 · If there is data then the result will already be a number so there's no conversion to be done. 2nd question:-. 127. net to better benefit the one that asked the question. Dim dt As New DataTable. OfType(Of DataRow)() The Rows property returns a DataRowCollection , that implements (through inheritance) the IEnumerable interface but not the IEnumerable(Of T) interface, that's why you can't use most of linq over I need to find the min and max value in an array. For Each row As DataGridViewRow In DataGridView1. Compute("SUM(Amount)", "Day = 3") Day will not be limited to 3. CreateCommand. Compute("SUM(TotalAmount)", "") Jun 16, 2014 · You can use Linq extension methods (System. ExecuteScalar which gets the value. GetType() Is GetType(DBNull) Then 'Do something End If That being said, the DBNull in your code above may also happen in the dtpay. I want to compare if all values of first datatable exist in second datatable using the best technique. The maximum number of rows that a DataTable can store is 16,777,216. Next. DataTable Select. Field(Of Integer)("productgroup") Into Group. CommandText = "SELECT MAX(CAST(points AS UNSIGNED)) FROM score". Dec 22, 2009 · 1. According to Your comment - if You want to calculate max value from a string column which holds numbers (don't get it why) You can go Jul 5, 2019 · 1. Because there is too much data in my datatable. Aug 22, 2013 · The range table with sample data: Dim rangeTable = New DataTable() rangeTable. Dim highestValue = DataGridView1. So far so good. CommandText = "select * from field_copy_no order by copy_no1". Dim dtStudents As New DataTable . Net: If dtpay. searchedValue = MyDataTable1. AsEnumerable(). cmd. Compute("SUM(Price)", $"[Vat_Per] = {RATE} AND [Sale_Free] = 'R'") The following example shows how to create a new application that performs queries against a SQL Server database. Dot Net Perls is a collection of tested code examples. Nov 27, 2015 · You can set the primary key of a table by: Dim table As New DataTable() table. I have data table Month, campaign, sales, leads, gross 1 1 5 10 1000 1 2 0 5 0 2 1 2 0 300 2 2 1 3 200 Jun 16, 2015 · Say you had a table in SQL and you wanted to find all the rows where a particular column could be one of 3 options. Rows (abc). 7. ConnectionStrings("ConnStringDb"). May 13, 2016 · You can use GetType() to check if an object is DBNull in VB. For example, you can restrict the data type to integers, or strings, or decimals. A possible result: Dim separator As String = ", ". value3 username. columns. var result = from row in tbl. Dim NewDataSet As DataTable = view. 0 = f_name. Data. Net datatable, select Jul 22, 2011 · This is how to retrieve a Column Name from a DataColumn: MyDataTable. Using sqlCommand As New MySqlCommand() With sqlCommand. Count) As String. I have created one that return Dictionary<Column-Index, MaxLength>. Apr 28, 2020 · Private Sub Button1_Click(sender As Object, e As EventArgs) Handles Button1. 19. edited Mar 26, 2010 at 20:49. Because they result in shorter code, they are often preferable. F0r3v3r-A-N00b. Max(maxValue, Convert. Field(Of String)("Name") Distinct. Here's an example. And then a button get max, which will use the text box with column name. edited Jul 26, 2020 at 10:45. Aug 20, 2015 · Try this if you are using a strongly-typed DataTable: For Each Row As StronglyTypedDataRow In dt. Length Mar 1, 2011 · I want to copy just "Col2, Col3" into another DataTable which has a primary key "ID". Now i need to select max and min value of a column. Mar 3, 2016 · 2. Dim Max as Double. Cells( "sal" ). Feb 12, 2020 · It would probably be better to sort the grouped rows by price descending and take the first row, rather than running Max three times, using it to filter the grouped rows, and then projecting a single column from it. that return the same max value . Value) {. Dec 23, 2019 · how to get the max value from a datatable field (Start) with 2 filters (Test = 1 and Start < 100)? i actually use : Dim a As String = dt. name(i) = column. Group. Net: Sep 11, 2015 · 2. BinarySearch(key) If index >= 0 Then. Select row. Value. Apr 28, 2014 · If you want to create dynamically/runtime data table in VB. VB. Oct 8, 2013 · I am trying to retrieve all of the distinct values from a particular column in a datatable. Sort = "ColumnName" ' Sort your data view. Field<int>("SomeIntegerColumn"); EDIT. 2k 18 65 83. Expression. What is the best way to copy them. Compute("SUM(TotalAmount)", "") Apr 9, 2011 · If all your columns are numeric-columns you might want this: You could use DataTable. Mar 26, 2010 · All you need is. currently i am using for each but one time it is FALSE and Second time TRUE so it does not look practical. Jul 5, 2019 · Current code: double maxValue = 0; foreach (DataRow dr in dataTable. Here's the code: Dim table As DataTable = CartDataSet. If You want to get highest Value from DataTable in code not in sql, then You can just use linq like below: int highestNumber = dtApprovalNumber. ToTable() ' Put your dataview into a new datatable. Count <> 0 Then. OP knows the position of the field and want to pull the value directly, not loop through each row to get to it, which is inefficient. Read() If empid = IsDBNull(dr("MAXIMUM")) Then. If there is no data then you get DBNull. index. Public Class Program_2_Grade Dim max As Integer Dim min As Integer Dim average As Sep 2, 2013 · Dim rows() = msgTable. ValueField(Object value) at System. Dim ds As New DataSet. I found the below C# code on SO but I was unable to translate it to VB. First example. WHERE predicates; Is it possible to obtain the same result with Entity Framework. OfType( Of DataGridViewRow). Show(maxValue. Columns(1). Dim clientname = (From cntable In t Aug 13, 2018 · The goal was to get the next "unassigned" productid and automatically put it in a textbox right after the previous adding of a record. Furthermore this will return the value of column 3 for each row, overwriting each time, and leaving OP with the value of l, rather than the value of d, the value they want. Why is my data not saved to my database? | MSDN Data Walkthroughs. ToString) Column names and numbers don't have single quotes around them. That way you do not have to sort, but you can still get the Max value. And that is first six column of my datatable – Dim empid As Integer. Here it is in VB. Daniel Manta. The . ToString()) End IF Or you can use ExecuteReader, Dim dr2 As OracleDataReader = cmd2. I want to get the currency Id and currency Name from the currency table where currency is local currency, and assign the currency id and name to a text boxes on the form: Mar 22, 2018 · Dim dtMatrix As DataTable = New DataTable() '' Populate code goes here Dim dtRows As IEnumerable(Of DataRow) = dtMatrix. Select("PrimaryKey = '10'") Row(0)("Description") = Description. The column name in the datatable is "Count". RowsFilter but no success. Sort() Return index. ToInt32(DataSet. ToInt32(row. Max and Math. Period = row. Jul 20, 2015 · here is what I've tried so far. DataSource = dv. The item tells which index. Select( String. Select("State = " + "'" + State + "'") Dim TempDt As New DataTable. Mar 24, 2017 · For example: Dim dt As DataTable = TryCast(Session("dt"), DataTable) If dt. To get the name of all DataColumns within your DataTable: Dim name(DT. Apr 30, 2013 at 5:08. We define GetTable—this returns a new DataTable. Dim a As String = dt. ToString & " = " & value. dr = cmd2. Aug 3, 2014 · I am trying to get the sum of the column TotalAmount in my DataTable dt but I always get this error: Object reference not set to an instance of an object. private Dictionary<int, int> TableColumnWidth(DataTable dt) Dictionary<int, int> result = new(); for (int i = 0; i < dt. The Rows tells which row of the datatable. totalCount += Double. FirstOrDefault(); List<MasterRecordResultClaim> records = new List<MasterRecordResultClaim>(); foreach (var bestresult in bests Mar 21, 2015 · You can access the data from data view as below. ColumnName), Nothing). Not an answer but too big for a comment. Nov 15, 2011 · Using LINQ might also be an option here. Select("ID = " & idOfMessage) if rows. public System. EventDescriptionGenderView into g orderby g. Jun 17, 2010 · The accepted answer is correct, though it should have been given in vb. If Rows. Apr 9, 2014 · 0. Select("ID=1 and FirstName='Karthik'", "ID Mar 9, 2016 · But the data for a person will be in the rows, the part you want will be at the position indicated by the column. Tables("dt_Lodging"). Parse(DataTable1. Open() 'since you are only retrieving a single value. Thus, check also where the DBNull occurs. Compute("Max(Start)", "Test = 1") TextBox_Start. ToString) Next. Group p By transactionTypeName = p(0) _. ToDouble(p(1))) _. Max(AddressOf Enumerable. AsEnumerable() Select row. For more information, see Aggregate Clause and Group By Clause. Item ("Name"). Select("ID = MAX(ID)"); This will return a DataRow[] array - but it should typically only contain a single row (unless you have multiple rows with the same, maximum value). x = grp. Net to retrieve data from a database, do some calculations, and then show this data in a datagridview. For Each row As DataGridViewRow In Dec 12, 2022 · 0. You could always use the . This will return the first column from the first row of the first table as an Object. Cast(Of DataColumn) Order By c. Jul 30, 2011 · So as the other answers indication you need to use: int max = roomCollection. ds. MsgBox(row(0)(1). John M Gant. Max(); answered Oct 10, 2011 at 12:14. EventArgs) Handles Me. MaxLength. Nov 28, 2018 · With the DataTable. myconnection. So, we have this code: Dim rstData As New DataTable Mar 4, 2012 · You can't access "price" that way since there's no price member on DataRow. Row = DataSet1. Count; i++) Jun 18, 2013 · i tried the coding below it dosent work. How can I convert 10 lines with three columns into a DataSet/DataTable? Lines are something like this: Item-1, $100, 44 Item-2, $42, 3 etc Sep 15, 2015 · 4. blogspot. remove column, add column. Rows(i). answered Mar 26, 2010 at 20:41. Max(dr => (int)dr["room"]); This says for each DataRow select the integer value for room and get the maximum room value. Add("Id", typeof(int)); convert the strings to Protected Sub Page_Load(ByVal sender As Object, ByVal e As System. DataRow[] Select (); Returns. link_id & " - " & Row. If you want to get the string inside the field cln_name, you need first to transform the result of your query to an enumeration of strings, then materialize the element. NET programs, DataTable has columns and rows properties. Then you could either use DataTable. Tables("dt") Dim result As Integer result = table. Select c. CopyToDataTable() ds. Select ("DT_ALTERDATE=MAX (DT_ALTERDATE) and C 127. Value)) In C# (from the top of my head): C#. Click Dim dt = DirectCast(DataGridView1. Matías Fidemraizer. Once this is done, I don't need to Apr 11, 2015 · The problem is that you have created string columns but you want to get the max-values according to their numeric value. In data-table we can do this by using this. If your DataTable looks like this : ColumnName1 ColumnName2. dt. OrderByDescending(z => z. cs. But I don't want to cycle through all the elements in MaxStep. ColumnName. After that, we have a text box to show the results. Max) Apr 4, 2016 · How To Display The Max Value In A DataGridView Column In VB NETSource Code: http://1bestcsharp. dll. DataSource, DataTable) Dim maxValue = Aggregate r In dt. Add("Min", GetType(Int32)) rangeTable. SelectCommand = New SqlCommand("SELECT StudentID, Name FROM Students", myConnection) . Jul 1, 2011 · 17. Dim x As New DataTable. Add 5 times to populate the collection with data. string val = (string)DataView[RowIndex][column index or column name in double quotes] ; // or. id & " - " & Row. Max(x => x["price"]) }; Nov 16, 2023 · This is not correct. com/2016/04/vb-net-datagridview-column-maximum-value. Connection = SQLConnection. Net: Dim dt As New DataTable:Dim dv As New DataView(dt):dv. ExecuteScalar) Catch ex As OleDbException. {. I have 2240 rows and I have 6 distinct values in the "Count" column. 'Do something ! End If. Rows. Then, you can check if a value exists in the index quickly with a binary search, like this: Dim index As Integer = index. Max() function is a part of the Linq (Language Integration Query) added in . Count) For Each row As DataRow in table. ExecuteScalar() IF Not IsNoThing(value) Then result=Decimal. Dates = dateGroup, . When the GetTable function is invoked, it creates a new DataTable and adds 3 columns to it. Pages are continually updated to stay current, with code correctness a top priority. Max( Function (row) Convert. 'you can used . Overloads. Max(r => r. If you want to compare your TextBox1. Select transactionTypeName, totalForType. ConnectionString Dim i As Integer Dim con As New SqlConnection(strcon) da = New SqlDataAdapter("select empName from empMaster_VB", con) ds = New Jan 11, 2019 · Dim query As String = "Select MAX(Row) from Table2". ToString () Next. Net DataTable. toName = "". thanx all got it DataRow [] dRows = dt. The best way is to store the corrrect type in the first place. Tables(0). But I think you should use a more correct approach using a simple ExecuteScalar that doesn't return the entire datatable but just the first row and first column of a query. Columns) {. This is my For loop: For i As Integer = 0 To DTPerson. Compute(String. Apr 24, 2010 · at System. You can do that using LINQ FirstOrDefault method - it returns first element of collection or default value ( Nothing for all reference types) it collection hasn't got results: Dim firstRow As DataRow = dttable. Dim SQlDa As SqlDataAdapter = New SqlDataAdapter(SqlCmd) SQlDa. net code? Dim rs As MySqlDataReader. items. Dim i As Integer = 0. Also doesn't work. Dec 31, 2003 · Hi. Sep 28, 2010 · Re: Select distinct values from a DataTable? Assuming . Select () Source: DataTable. Also, it kind of looks like you don't want the max from the column since it would be a sum of the column value so: Dim Sum, Max as Double. Select(i. 2,933 4 27 38. maxValue = Math. If you want strict comparison, case-sensitive and exact word: Dim selectedCells = DataGridView1. Compute to Sum all values in the column. For Each column As DataColumn In DT. AsEnumerable Into MaxID = Max(r("ID")) '"ID" is the name of a column MessageBox. DataRow [] An array of DataRow objects. ToString) End Sub Jul 9, 2015 · I have a datagridview control on my windows form. SelectCommand = New SqlCommand ("SELECT StudentID, Name FROM Students", myConnection) da. Field[T](DataRow row, String columnName) This most definitely confirms that the problem is not inside linq, but in the actual data that you're trying to convert. Second call is the exception message, definitely a data conversion problem: Jan 1, 2021 · If there is data then the result will already be a number so there's no conversion to be done. Rows("value3"). datatable. Thanks in advance. And that is first six column of my datatable – Use linq and set the data table as Enumerable and select the fields from the data table field that matches what you are looking for. net Code: Dim names = From row In myDataTable. Now I want to add up values from columns where another column in the same row has a specific text. Looking for the fastest way. Ordinal. row. Item("ColumnName2"). Jan 7, 2012 · this is not LINQ but filtering datatable. For Each chkRow As DataRow In chk. Field(Of String)(1) toID = 0. 1. Compute("Max(Start)", "Test = 1" and "Start < 100") TextBox_Start. Tables. Yr = row. Parse(value. public class Person. Dim filteredRows = From row In datatable2. ColumnName])); Dec 31, 2003 · Getting max value of a column in a datatable? Hi. C# Copy. Jul 12, 2020 · 6. DataRowExtensions. Field<int>("Id")); How can i achieve this in datagridview. Max) Alternate syntax using a lambda instead of a method group : items. If Session("dt") has never been set or is lost in memory for some reason, dt. dz kj sx zd ay do jk ew vw zk