Howto Add a row to a Datagrid

duc · Apr 28, 2012

Hi, Can someone please tell me how I can add rows to a datagrid (one at a time) by clicking a button. I can add one row, but if I add another one it replaces the first?? my code: ****************************************** Public Cart As New DataTable() Sub Page_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load If Page.IsPostBack Then myDatagrid.AutoGenerateColumns = True Cart.Columns.Add(New DataColumn("Item", GetType(String))) Cart.Columns.Add(New DataColumn("Price", GetType(String))) End If End Sub Private Sub btnAddItem_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btnAddItem.Click Dim dr As DataRow = Cart.NewRow() dr(0) = myDropdownlist.SelectedItem.Value dr(1) = myDropdownlist.SelectedItem.Text Cart.Rows.Add(dr) myDatagrid.DataSource = Cart myDatagrid.DataBind() End Sub ****************************************** Thanx by advance. This is a complete example of adding blank (or filled) rows to a datagrid as needed. You should be able to pick out the code you need. Good Luck. <%@ Page Language="VB" Debug = "True" %> <%@ Import NameSpace="System.Data" %> <%@ Import NameSpace="System.Xml" %> <SCRIPT RUNAT="SERVER"> ' ================================================== =============== ' DEMO OF WORKING WITH DATA IN A DISCONNECTED STATE, THEN SAVING CHANGES ' BACK TO SOURCE DATABASE WHEN YOU'RE READY. ' ' DATAGRID HAS ABILITY TO ADD BLANK ROWS AS NEEDED. ' ================================================== =============== Dim objDataSet As New DataSet("objDataSet") Dim xmlTestTable As DataTable = objDataSet.Tables.Add("xmlTestTable") Dim strXML As String Sub Page_Load(obj as Object, e as EventArgs) ' === SPECIFY COLUMNS SINCE A BLANK ROW CAN BE ADDED. With objDataSet.Tables("xmlTestTable") .Columns.Add("FName", System.Type.GetType("System.String")) .Columns.Add("LName", System.Type.GetType("System.String")) End With ' === FIRST TIME THRU, SAVE A COPY OF DATASET TO VIEWSTATE. If Not Page.IsPostBack Then FirstRow() objDGrid.EditItemIndex = 0 BindIt() End If GetIt() ' GET DATA FROM VIEWSTATE. End Sub ' === SaveIt SUB CONVERTS DATASET TO XML STRING AN PUTS IN VIEWSTATE. Sub SaveIt() strXML = objDataSet.GetXml() ViewState("strData")=strXML End Sub ' === GetIt SUB GETS XMLSTRING FROM VIEWSTATE AND RECREATES DATASET. Sub GetIt() If Not ViewState("strData") Is Nothing then objDataSet.Clear() strXML = ViewState("strData").ToString() Dim strReader As New System.IO.StringReader(strXML) objDataSet.Readxml(strReader) End If End Sub ' === ADD A NEW ROW WHEN PAGE IS FIRST LOADED. Sub FirstRow() GetIt() Dim AddaRow As DataRow = objDataSet.Tables("xmlTestTable").NewRow() AddaRow.Item("FName") = " " AddaRow.Item("LName") = " " objDataSet.Tables("xmlTestTable").Rows.Add(AddaRow) SaveIt() End Sub ' === ADD A NEW ROW TO DATASET. BLANK ROW ENTRY IS OK. Sub AddRow(obj as Object, e as EventArgs) GetIt() Dim AddaRow As DataRow = objDataSet.Tables("xmlTestTable").NewRow() AddaRow.Item("FName") = " " AddaRow.Item("LName") = " " objDataSet.Tables("xmlTestTable").Rows.Add(AddaRow) SaveIt() ' SAVE REVISED DS TO VIEWSTATE. BindIt() ' REBIND REVISED DS TO GRID. End Sub ' === STANDARD SUB FOR BINDING DATASET TO DATAGRID. Sub BindIt() objDGrid.DataSource = objDataSet.Tables("xmlTestTable") objDGrid.DataBind() End Sub ' === EDIT LINK CLICKED ON DATAGRID. PUT GRID IN EDIT MODE. Sub EditGrid(obj as object, e as DataGridCommandEventArgs) GetIt() objDGrid.EditItemIndex = e.Item.ItemIndex SaveIt() BindIt() End Sub ' === CANCEL LINK CLICKED ON DATAGRID. Sub CancelGrid(obj as object, e as DataGridCommandEventArgs) GetIt() objDGrid.EditItemIndex = -1 SaveIt() BindIt() End Sub ' === UPDATE LINK CLICKED ON DATAGRID. UPDATE DATASET WITH DATAGRID EDITS. Sub UpDateGrid(obj As object, e As DataGridCommandEventArgs) Dim gRow As Integer = objDGrid.EditItemIndex ' ROW NUMBER OF ROW IN EDIT MODE. Dim txtFName As TextBox = e.Item.Cells(0).Controls(0) Dim txtLName As TextBox = e.Item.Cells(1).Controls(0) GetIt() ' GET COPY OF DS objDataSet.Tables("xmlTestTable").Rows(gRow)(0) = txtFName.text objDataSet.Tables("xmlTestTable").Rows(gRow)(1) = txtLName.text objDGrid.EditItemIndex = -1 ' TAKE GRID OUT OF EDIT MODE. SaveIt() ' SAVE CHANGES TO DS BindIt() ' RE-BIND GRID. End Sub ' === SUB TO SAVE DATASET CHANGES BACK TO SOURCE DATABASE. Sub SaveAll(obj as Object, e as EventArgs) Response.Write("Your DataBase Update Sub Would Run At This Point") End Sub </SCRIPT> <HTML><BODY> <FORM Runat="Server" EnableViewState = "True" > <ASP:Button ID="btnSubmit" Text="Add New Row" Runat="Server" OnClick="AddRow" /> <ASP

ataGrid ID="objDGrid" Runat="Server" OnEditCommand = "EditGrid" OnCancelCommand = "CancelGrid" OnUpdateCommand = "UpdateGrid" Width = "350" AutoGenerateColumns = "False"> <Columns> <ASP:BoundColumn HeaderText = "First Name" DataField = "FName"> <ItemStyle Width = "150"/> </ASP:BoundColumn> <ASP:BoundColumn HeaderText = "Last Name" DataField = "LName"> <ItemStyle Width = "150"/> </ASP:BoundColumn> <ASP:EditCommandColumn EditText = "Add/Edit" CancelText = "Cancel" UpdateText = "Enter" ItemStyle-Wrap = "False" HeaderText = "Add/Edit" > <ItemStyle Font-Size = "8"/> </ASP:EditCommandColumn> </Columns> </ASP

ataGrid> </FORM> </BODY></HTML>Thanx, it works.

Howto Add a row to a Datagrid

duc

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