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[Solved] Invalid Cast Exception using Custom Edit Form in Grid

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Grid

This is a migrated thread and some comments may be shown as answers.

Ismail asked on 01 Jul 2009, 09:47 AM

HI
I have the following code for a grid that i'm using to manage Users. I created a custom edit form with a few textobxes and a checkbox, this works 100% when editing an item, however i get an error(Invalid Cast Exception) when trying to create a new User, this error is thrown while the custom form is being loaded.
I know that this is caused by the asp checkbox that i'm using in the edit form, Please assist me.
Thanks in advance :)

    
            <%@ Page Language="C#" AutoEventWireup="true" CodeFile="AdminPage.aspx.cs" Inherits="AddEditUsers" %> 
        
            <%@ Register assembly="Telerik.Web.UI" namespace="Telerik.Web.UI" tagprefix="telerik" %> 
        
            <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"> 
        
            <html xmlns="http://www.w3.org/1999/xhtml"> 
        
            <head runat="server"> 
        
                <title>All Users</title> 
        
                <style type="text/css"> 
        
                    .style1 
        
                    { 
        
                        width: 100%; 
        
                        height: 68px; 
        
                    } 
        
                </style> 
        
            </head> 
        
            <body> 
        
                <form id="form1" runat="server"> 
        
                <asp:ScriptManager ID="ScriptManager1" runat="server"> 
        
                </asp:ScriptManager> 
        
                <div> 
        
                <table class="style1"> 
        
                    <tr> 
        
                        <td> 
        
                            &nbsp;</td> 
        
                    </tr> 
        
                    <tr> 
        
                        <td> 
        
                            <telerik:RadGrid ID="RadGrid1" runat="server" AutoGenerateColumns="False"  
        
                                DataSourceID="SqlDataSource1" GridLines="None"  
        
                                Skin="Vista" AllowAutomaticDeletes="True" AllowAutomaticUpdates="true"  
        
                                AllowAutomaticInserts="true" AllowMultiRowEdit="True"> 
        
            <MasterTableView datakeynames="UserId" datasourceid="SqlDataSource1" EditMode="PopUp"  commanditemdisplay="Top" > 
        
            <RowIndicatorColumn> 
        
            <HeaderStyle Width="20px"></HeaderStyle> 
        
            </RowIndicatorColumn> 
        
            <ExpandCollapseColumn> 
        
            <HeaderStyle Width="20px"></HeaderStyle> 
        
            </ExpandCollapseColumn> 
        
                <Columns> 
        
                    <telerik:GridButtonColumn ConfirmText="Are You Sure You Want To Delete This User?" ButtonType="ImageButton" CommandName="Delete" Text="Delete" UniqueName="DeleteColumn1"> 
        
                                                    <HeaderStyle Width="20px" /> 
        
                                                    <ItemStyle HorizontalAlign="Center" /> 
        
                    </telerik:GridButtonColumn> 
        
                    <telerik:GridBoundColumn DataField="UserId" DataType="System.Int32"  
        
                        HeaderText="UserId" ReadOnly="True" SortExpression="UserId" UniqueName="UserId" Visible="false"> 
        
                    </telerik:GridBoundColumn> 
        
                    <telerik:GridBoundColumn DataField="UserName" HeaderText="User Name"  
        
                        SortExpression="UserName" UniqueName="UserName"> 
        
                    </telerik:GridBoundColumn> 
        
                    <telerik:GridBoundColumn DataField="Password" HeaderText="Password"  
        
                        SortExpression="Password" UniqueName="Password"> 
        
                    </telerik:GridBoundColumn> 
        
                    <telerik:GridCheckBoxColumn DataField="IsAdmin" HeaderText="Administrator" 
        
                                    DataType="System.Boolean"> 
        
                                </telerik:GridCheckBoxColumn> 
        
                    <telerik:GridEditCommandColumn ButtonType="ImageButton"> 
        
                    </telerik:GridEditCommandColumn> 
        
                    <telerik:GridHyperLinkColumn></telerik:GridHyperLinkColumn> 
        
                </Columns> 
        
                 <EditFormSettings EditFormType="Template"> 
        
                 <EditColumn UniqueName="EditCommandColumn1"></EditColumn> 
        
                 <FormTemplate> 
        
                 <table id="EditTable" cellspacing="1" cellpadding="1" border="0"> 
        
                 <tr>  
        
                    <td>User Name</td> 
        
                    <td> <asp:TextBox ID="txtUserName" runat="server" MaxLength="10" Text='<%#Bind("UserName") %>'></asp:TextBox></td> 
        
                 </tr> 
        
                 <tr> 
        
                    <td>Password</td> 
        
                    <td> <asp:TextBox ID="txtPassword" runat="server" MaxLength="15" Text='<%#Bind("Password") %>'></asp:TextBox></td> 
        
                 </tr> 
        
                 <tr> 
        
                    <td></td> 
        
                    <td> <asp:CheckBox ID="chkIsAdmin" runat="server" Text="Administrator" Checked='<%#Bind("IsAdmin") %>'></asp:CheckBox></td> 
        
                 </tr> 
        
                 <tr> 
        
                    <td><asp:Button id="btnUpdate" runat="server" Text='<%# (Container is GridEditFormInsertItem) ? "Insert" : "Update" %>' CommandName='<%# (Container is GridEditFormInsertItem) ? "PerformInsert" : "Update" %>'/></td> 
        
                    <td><asp:Button ID="btnCancel" runat="server" CausesValidation="false" CommandName="cancel" Text="Cancel"/></td> 
        
                 </tr> 
        
                 </table> 
        
                 </FormTemplate> 
        
                 </EditFormSettings> 
        
            </MasterTableView> 
        
                                <ClientSettings> 
        
                                    <Selecting AllowRowSelect="True" /> 
        
                                </ClientSettings> 
        
            <FilterMenu EnableTheming="True"> 
        
            <CollapseAnimation Type="OutQuint" Duration="200"></CollapseAnimation> 
        
            </FilterMenu> 
        
                            </telerik:RadGrid> 
        
                            <asp:SqlDataSource ID="SqlDataSource1" runat="server"  
        
                                ConflictDetection="CompareAllValues"  
        
                                ConnectionString="<%$ ConnectionStrings:lawsocConnectionString %>"  
        
                                DeleteCommand="DELETE FROM [tbUsers2] WHERE [UserId] = @original_UserId AND [UserName] = @original_UserName AND [Password] = @original_Password AND [IsAdmin] = @original_IsAdmin"  
        
                                InsertCommand="INSERT INTO [tbUsers2] ([UserName], [Password], [IsAdmin]) VALUES (@UserName, @Password, @IsAdmin)"  
        
                                OldValuesParameterFormatString="original_{0}"  
        
                                SelectCommand="SELECT [UserId], [UserName], [Password], [IsAdmin] FROM [tbUsers2]"  
        
                                UpdateCommand="UPDATE [tbUsers2] SET [UserName] = @UserName, [Password] = @Password, [IsAdmin] = @IsAdmin WHERE [UserId] = @original_UserId AND [UserName] = @original_UserName AND [Password] = @original_Password AND [IsAdmin] = @original_IsAdmin"> 
        
                                <DeleteParameters> 
        
                                    <asp:Parameter Name="original_UserId" Type="Int32" /> 
        
                                    <asp:Parameter Name="original_UserName" Type="String" /> 
        
                                    <asp:Parameter Name="original_Password" Type="String" /> 
        
                                    <asp:Parameter Name="original_IsAdmin" Type="String" /> 
        
                                </DeleteParameters> 
        
                                <UpdateParameters> 
        
                                    <asp:Parameter Name="UserName" Type="String" /> 
        
                                    <asp:Parameter Name="Password" Type="String" /> 
        
                                    <asp:Parameter Name="IsAdmin" Type="String" /> 
        
                                    <asp:Parameter Name="original_UserId" Type="Int32" /> 
        
                                    <asp:Parameter Name="original_UserName" Type="String" /> 
        
                                    <asp:Parameter Name="original_Password" Type="String" /> 
        
                                    <asp:Parameter Name="original_IsAdmin" Type="String" /> 
        
                                </UpdateParameters> 
        
                                <InsertParameters> 
        
                                    <asp:Parameter Name="UserName" Type="String" /> 
        
                                    <asp:Parameter Name="Password" Type="String" /> 
        
                                    <asp:Parameter Name="IsAdmin" Type="String" /> 
        
                                </InsertParameters> 
        
                            </asp:SqlDataSource> 
        
                        </td> 
        
                    </tr> 
        
                    <tr> 
        
                        <td> 
        
                            &nbsp;</td> 
        
                    </tr> 
        
                    <tr> 
        
                        <td> 
        
                            &nbsp;</td> 
        
                    </tr> 
        
                </table> 
        
                </div> 
        
                </form> 
        
            </body> 
        
            </html>

2 Answers, 1 is accepted

answered on 01 Jul 2009, 11:35 AM

Hello Ismail,

The reason for this error is that your grid instance can not bind a checkbox value for the newly inserted item through theEval()/Bind() syntax you hard-coded.This can be fixed by presetting the default value of the checkbox when binding to a grid item on the RadGrid.InitInsertCommandName command as shown below:

c#:

                    protected void RadGrid1_ItemCommand(object source, Telerik.Web.UI.GridCommandEventArgs e)         
            {         
                if ((e.CommandName == RadGrid.InitInsertCommandName))         
                      {         
                    e.Canceled = true;         
                    //Prepare an IDictionary with the predefined values         
                    System.Collections.Specialized.ListDictionary newValues = new System.Collections.Specialized.ListDictionary();               
                     
                    //set initial checked state for the checkbox on init insert         
                    newValues["IsAdmin"] = false;         
                     
                    //Insert the item and rebind         
                    e.Item.OwnerTableView.InsertItem(newValues);         
                }         
            }         
                     

Thanks

Shinu.