📄 remove-delete-rows.aspx
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<%@Page Language="VB"%>
<%@Import Namespace="System.Data" %>
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN">
<html>
<title>Removing versus Deleting Rows in a DataTable</title>
<!-- #include file="..\global\style.inc" -->
</head>
<body bgcolor="#ffffff">
<span class="heading">Removing versus Deleting Rows in a DataTable</span><hr />
<!--------------------------------------------------------------------------->
<b>The original table contents</b>:
<asp:datagrid id="dgrResult1" runat="server" /><br />
<b>The table contents after Rows(1).Delete()</b>:
<asp:datagrid id="dgrResult2" runat="server" /><br />
<b>The table contents after RejectChanges()</b>:
<asp:datagrid id="dgrResult3" runat="server" /><br />
<b>The table contents after Rows.Remove(1)</b>:
<asp:datagrid id="dgrResult4" runat="server" /><br />
<b>The table contents after RejectChanges()</b>:
<asp:datagrid id="dgrResult5" runat="server" /><br />
<script language="vb" runat="server">
Sub Page_Load()
'create a new empty Table object
Dim objTable As New DataTable("NewTable")
'define four columns (fields) within the table
objTable.Columns.Add("ISBN", System.Type.GetType("System.String"))
objTable.Columns.Add("Title", System.Type.GetType("System.String"))
objTable.Columns.Add("PublicationDate", System.Type.GetType("System.DateTime"))
objTable.Columns.Add("Quantity", System.Type.GetType("System.Int32"))
'declare a variable to hold a DataRow object
Dim objDataRow As DataRow
'create a new DataRow object instance in this table
objDataRow = objTable.NewRow()
'and fill in the values
objDataRow("ISBN") = "1234567800"
objDataRow("Title") = "Professional Video Recorder Programming"
objDataRow("PublicationDate") = "2001-03-01"
objDataRow("Quantity") = "3956"
objTable.Rows.Add(objDataRow)
'repeat to add two more rows
objDataRow = objTable.NewRow()
objDataRow("ISBN") = "1234567801"
objDataRow("Title") = "Professional WAP Phone Programming"
objDataRow("PublicationDate") = "2001-06-01"
objDataRow("Quantity") = "29"
objTable.Rows.Add(objDataRow)
objDataRow = objTable.NewRow()
objDataRow("ISBN") = "1234567802"
objDataRow("Title") = "Professional Radio Station Programming"
objDataRow("PublicationDate") = "2001-04-01"
objDataRow("Quantity") = "10456"
objTable.Rows.Add(objDataRow)
'call AcceptChanges to accept the changes to the table so far
objTable.AcceptChanges()
'assign the DataTable's DefaultView object to the DataGrid control
dgrResult1.DataSource = objTable.DefaultView
dgrResult1.DataBind() 'and bind (display) the data
'now Delete the second row and display the contents again
objTable.Rows(1).Delete()
dgrResult2.DataSource = objTable.DefaultView
dgrResult2.DataBind()
'call RejectChanges to restore the deleted row
objTable.RejectChanges()
dgrResult3.DataSource = objTable.DefaultView
dgrResult3.DataBind()
'now Remove the second row from the table
'note that this is a method of the Rows collection not the Row object
objTable.Rows.RemoveAt(1)
dgrResult4.DataSource = objTable.DefaultView
dgrResult4.DataBind()
'call RejectChanges - the deleted row is not restored
objTable.RejectChanges()
dgrResult5.DataSource = objTable.DefaultView
dgrResult5.DataBind()
End Sub
</script>
<!--------------------------------------------------------------------------->
<!-- #include file="..\global\foot.inc" -->
</body>
</html>
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