Prevent concurrency conflict : GridView « Data Binding « ASP.NET Tutorial






The ConflictDetection property can have one of the following two values:

CompareAllValues

OverwriteChanges


<%@ Page Language="C#" %>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.1//EN"
"http://www.w3.org/TR/xhtml11/DTD/xhtml11.dtd">

<script runat="server">
    protected void srcProducts_Updated(object sender, SqlDataSourceStatusEventArgs e)
    {
        if (e.AffectedRows == 0)
            lblMessage.Text = "Could not update record";
    }
</script>

<html xmlns="http://www.w3.org/1999/xhtml" >
<head id="Head1" runat="server">
    <title>Concurrency</title>
</head>
<body>
    <form id="form1" runat="server">
    <div>

    <asp:Label ID="lblMessage" EnableViewState="false" runat="server" />

    <asp:GridView
        id="grdProducts"
        DataSourceID="srcProducts"
        DataKeyNames="Id"
        AutoGenerateEditButton="true"
        Runat="server" />

    <asp:SqlDataSource
        id="srcProducts"
        ConflictDetection="CompareAllValues"
        OldValuesParameterFormatString="original_{0}"
        ConnectionString="<%$ ConnectionStrings:Products %>"
        SelectCommand="SELECT Id,Title,Director FROM Products"
        UpdateCommand="UPDATE Products SET Title=@Title, Director=@Director
                       WHERE Id=@original_Id AND Title=@original_Title AND Director=@original_Director"
        Runat="server" 
        OnUpdated="srcProducts_Updated" />

    </div>
    </form>
</body>
</html>

File: Web.config

<configuration>
  <connectionStrings>
    <add name="Products" 
         connectionString="Data Source=.\SQLEXPRESS;
         AttachDbFilename=|DataDirectory|MyDatabase.mdf;Integrated Security=True;User Instance=True" />
  </connectionStrings>
</configuration>








19.17.GridView
19.17.1.Set RowStyle and HeaderStyle for GridView
19.17.2.GridView DataBind
19.17.3.GridView with template
19.17.4.Using Programmatic DataBinding
19.17.5.Use asp:SqlDataSource and asp:GridView to edit database table
19.17.6.Pageable asp:GridView
19.17.7.Sortable GridView
19.17.8.DataBinding to GridView (C#)
19.17.9.Assign data source to GridView
19.17.10.Editing Data
19.17.11.Prevent concurrency conflict
19.17.12.Displaying a message when no records match.
19.17.13.Displaying a template when no records match.
19.17.14.Formatting the GridView Control
19.17.15.Using Fields with the GridView Control
19.17.16.Using the PagerStyle and PagerSettings objects in the GridView control
19.17.17.Using the Null value