Validation By Control ASP.Net

  1. Home
  2. ASP.Net
  3. Validation By Control
  4. Implement custom validation control event (VB net)
<%@ Page Language="VB" %>

    Protected Sub valProductCode_ServerValidate(ByVal source As Object, ByVal args As ServerValidateEventArgs)
        If args.Value.Length = 4 Then
            args.IsValid = True
        Else
            args.IsValid = False
        End If
    End Sub



    Show Validate Empty Text


    
    

    
            id="lblProductCode"
        Text="Product Code:"
        AssociatedControlID="txtProductCode"
        Runat="server" />
    
            id="txtProductCode"
        Runat="server" />
            id="valProductCode"
        ControlToValidate="txtProductCode"
        Text="(Invalid product code)"
        ValidateEmptyText="true"
        OnServerValidate="valProductCode_ServerValidate" 
        Runat="server" />
    
    
    
            id="btnSubmit"
        Text="Submit"
        Runat="server" />