Exclude Control from Page.Isvalid

Question

I have a few controls on a page that are all in the same validation group. Depending on certain conditions, one of these controls can be set to visible=false (and the user wont be able to input anything into it). If this happens, is there a way to remove said control from the validation group? Code like this:

if(testControl.Visible==false) testControl.ValidationGroup="";

does nothing. Yet, if I remove the validationgroup from the aspx page like so:

<asp:RequiredFieldValidator ID="testControl" runat="server" validationgroup=""></asp:RequiredFieldValidator> 

The page will validate. Is there a way around this?

Answer 1

Are you sure your code is being hit in the code-behind file? I mean, your control is really invisible when you check that condition?

if(testControl.Visible == false)
   testControl.ValidationGroup = string.Empty;

Put a breakpoint in testControl.ValidationGroup=""; and see if the debugger stops there.

Where is the code above? It should be inside the PageLoad method for example.

Call Page.Validate("NameOfYourValidationGroup") after that code.

What is the problem here I think:

You're setting this testControl with Visible = False and then you post back to the server. When you do testControl.ValidationGroup = string.Empty it'll have no effect because it has already posted back to the server:

From MSDN:

TextBox..::.ValidationGroup Property

Gets or sets the group of controls for which the TextBox control causes validation when it posts back to the server.

This way you should call this code testControl.ValidationGroup = string.Empty; when you hide your control setting it to Visible = false so that when the page loads again for the user the control won't be assigned to that ValidationGroup. Now, if you postback the page it should validate the way you want it.

Set testControl.CausesValidation = false too.

Answer 2

Does the following help?:

testControl.IsValid = true;

Use for ex. with:

Page.Validate();
// manual override of specific control
testControl.IsValid = true;

// Guard
if (! Page.IsValid) return; // Or do own custom logic
// else
// Do your stuff here...