Hi,

I have an asp:DropDownList and Requiredfield Validator as below.

<asp:DropDownList ID="DropDownList1" runat="server" >
           <asp:ListItem Selected="True" Text="Choose Items" Value=""></asp:ListItem>
            <asp:ListItem Text="aa" Value="aa"></asp:ListItem>
            <asp:ListItemText="bb" Value="bb"></asp:ListItem>
            <asp:ListItemText="cc" Value="cc"></asp:ListItem>
</asp:DropDownList>

<asp:RequiredFieldValidator ID="RequiredFieldValidator1" runat="server" ControlToValidate="DropDownList1"
            Display="Dynamic" ErrorMessage="Please Choose" EnableClientScript="true"></asp:RequiredFieldValidator>

There are two more radio buttons,which toggles the visibility of Drop Down list.

<asp:RadioButton ID="RadioButton1" runat="server" AutoPostBack="True" GroupName="Validate" OnCheckedChanged="RadioButton1_CheckedChanged" Text="Make Visible" />
<asp:RadioButton ID="RadioButton2" runat="server" AutoPostBack="True" GroupName="Validate" OnCheckedChanged="RadioButton2_CheckedChanged" Text="Make In-Visible" />

In last there is a Button. 

 <asp:Button ID="Button1" runat="server" Text="Button" OnClick="Button1_Click" />

Expected Behavior:
    - When DropDown is Visible - If button is clicked then system should popup Validator.
    - When DropDown is In-Visible - If button is clicked then system should not popup Validator.

Solution done by me:

Please help to achieve this in a more better way.

Thanks & Regards,

Arun Manglick || Tech Lead || AppliedSB – Digital Downloads || 620

arunmanglick:

There are two more radio buttons,which toggles the visibility of Drop Down list.

<asp:RadioButton ID="RadioButton1" runat="server" AutoPostBack="True" GroupName="Validate" OnCheckedChanged="RadioButton1_CheckedChanged" Text="Make Visible" />
<asp:RadioButton ID="RadioButton2" runat="server" AutoPostBack="True" GroupName="Validate" OnCheckedChanged="RadioButton2_CheckedChanged" Text="Make In-Visible" />

arunmanglick:

Expected Behavior:
    - When DropDown is Visible - If button is clicked then system should popup Validator.
    - When DropDown is In-Visible - If button is clicked then system should not popup Validator.

Do you want to solve it without a Postback? Then you need to hook up some javascript on the client that disables the validator. 

What you are doing is disabling the validator control itself. I just don't see how you hide the dropdown list. If you want to hide the dropdown list, just set its Visible property to false. When doing that, you can also set the CausesValidation property to false. In the handler for the other radioButton, do the opposite. Then the page will know that the dropdown list should not be validated.

Thanks for the reply. But 'CausesValidation'  will not serve the purpose.

Reason:

• There is no postback being attached to the drop down.
• Neither the need is to validate the page on Selection Change event of drop down. Instead the expectation is to validate/not-validate the page on 'Button' click.
  

As I have already marked, the working solution with me is as:
 

protected void RadioButton1_CheckedChanged(object sender, EventArgs e)
    {
        DropDownList1.Visible = true;        
        RequiredFieldValidator1.Enabled = true;      
    }
    protected void RadioButton2_CheckedChanged(object sender, EventArgs e)
    {
        DropDownList1.Visible = false;
        RequiredFieldValidator1.Enabled = false;      
    }  

I just need to know, Can we have some better solution than the mentioned or should I mark it as 'Resolved'

Regards,

Arun... 

On PostBack the whole page is validated, no matter which control caused the postback. I understand that you do not want to validate when changing the selection of the dropdown, this is why you do not have such an event. However, if you have a handler for the CheckedChanged event of the RadioButtonList, then it means you expect a postback to occur when you change the radio button. As you see, in the code I gave you I'm doing everything in the method for the radio button, not the dropdown. If you don't want a postback at all - use javascript. Otherwise, the code I gave you should work on postback not caused by DropDownList. Maybe I got confused and didn't understand what you want.