Required field validator not working

Question

I have used a required field validator followed by a regular expression validator but the required field validator is not working.....

<asp:TextBox ID="txtSummary" runat="server" TextMode="MultiLine" Width="700px"
    CssClass="txtStyle" Font-Names="Arial" MaxLength="1000" 
    ValidationGroup="Valtxt" TabIndex="2" Rows="4">
</asp:TextBox>

<asp:RegularExpressionValidator ID="regValSummary" runat="server"
    ControlToValidate="txtSummary" Display="Dynamic"
    ValidationExpression="[^&lt;&gt;&amp;#!]*" ValidationGroup="Valtxt">
        Invalid characters(&lt;&gt;&amp;#!) are not allowed
</asp:RegularExpressionValidator>

<asp:RequiredFieldValidator ID="reqvalSummary" runat="server"
    ControlToValidate="txtSummary" ErrorMessage="Summary is required"
    ValidationGroup="Valtxt" Display="Dynamic">
</asp:RequiredFieldValidator>

can anyone sees the problem???

ensure the validation group of the validation summary matches? — brumScouse, Nov 01 '10 at 13:14
FYI: Your ValidationExpression does not look right at all. Those characters should not be html encoded. Also, you need to reference the beginning and end of the string to ensure that all characters are taken into account. I think you want to use something more like ValidationExpression="^[^<>!]*$" — Buh Buh, Nov 01 '10 at 13:22

Ahmad Mageed · Accepted Answer · 2010-11-01T16:05:04.393

The RequiredFieldValidator is triggered by the client side onchange event. It sounds like you're expecting it to be triggered by the onblur event, such that tabbing away from the textbox would fire the validation.

Before jumping to that, I suspect this is what you are seeing and to validate that it's actually working you need to trigger onchange. To do so, enter some text in the textbox, tab away, tab back to it, clear the textbox, then tab away once more. You should now see the RequiredFieldValidator's error message since it's contents have changed.

Back to the onblur issue. To accomplish that behavior you could add the onblur attribute in your code-behind and have it call the ValidatorValidate(...) JavaScript method as follows:

void Page_Load(object sender, EventArgs e)
{
    txtSummary.Attributes.Add("onblur", "ValidatorValidate(" + reqvalSummary.ClientID + ")");
}

Alternately, you could accomplish the same thing in markup. First, add this script block:

<script type="text/javascript">
    function rfvBlur() {
        var rfv = document.getElementById("<%= reqvalSummary.ClientID %>");
        ValidatorValidate(rfv);
    }    
</script>

Second, update the <asp:TextBox.../> markup by adding onblur="rfvBlur()" so that it now looks like this:

<asp:TextBox ID="txtSummary" runat="server" TextMode="MultiLine" Width="700px" CausesValidation="true"
            CssClass="txtStyle" Font-Names="Arial" MaxLength="1000" ValidationGroup="Valtxt"
            TabIndex="2" Rows="4" onblur="rfvBlur()" />

Yet another option is to validate the entire ValidationGroup by adding the following attribute to your <asp:TextBox.../> markup (no additional script block needed):

onblur="Page_ClientValidate('Valtxt')"

Jerry Scannell's comment: "I'm trying to incorporate the rfvBlur() recommended but I can't figure out what ClientID was referencing in your example." — Peter O., Feb 28 '12 at 18:38
@PeterO. thanks for posting Jerry's comment. @Jerry: the `ClientID` is being called off of a `asp:RequiredFieldValidator` with an ID of `reqvalSummary`. You can see this validator in the original question, which is validating the `txtSummary` TextBox control. Use whatever `ID` you've given to your `RequiredFieldValidator` control. You'll need to do this for each control/validator you intend this to work with. — Ahmad Mageed, Feb 28 '12 at 19:24

score 4 · Answer 2 · answered Jan 22 '14 at 21:10

Adding this line to <appSettings> section of web.config worked for me (I had a problem when all validators stopped working when project was upgraded to .NET 4.5):

<add key="ValidationSettings:UnobtrusiveValidationMode" value="None" />

Source:

http://forums.asp.net/t/1876231.aspx?ASP+Net+4+5+Validation+Controls+not+working+with+AJAX+ToolkitScriptManager1

score 1 · Answer 3 · answered Nov 01 '10 at 16:09

1

Why don't you change the regular expression of the "RegEx" validator to check if the textbox is empty instead of use another validator?

Anyway probabily you have not specify ValidationGroup="Valtxt" for the button or the control that raise the postback. Just add ValidationGroup="Valtxt" to the button or the server control that raise the post to the page

answered Nov 01 '10 at 16:09

Massimiliano Peluso

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2

As odd as it may sound, the `RegularExpressionValidator` is not triggered on empty text and must be paired up with a `RequiredFieldValidator`. [From MSDN](http://msdn.microsoft.com/en-us/library/eahwtc9e.aspx): *"If the input control is empty, no validation functions are called and validation succeeds. Use a RequiredFieldValidator control to prevent the user from skipping an input control."* – Ahmad Mageed Nov 01 '10 at 16:14

score 0 · Answer 4 · answered Feb 14 '23 at 18:19

I put the following at the top of my btn_Click event handler (to prevent further code execution) and upon 'return', the rfv messages show...

        Page.Validate("your validation group");
        if (!Page.IsValid)
        {
            return;
        }

score -1 · Answer 5 · answered Jan 06 '11 at 13:34

<asp:TextBox ID="txtSummary" runat="server" TextMode="MultiLine" Width="700px"
    CssClass="txtStyle" Font-Names="Arial" MaxLength="1000" 
    TabIndex="2" Rows="4">
</asp:TextBox>

<asp:RegularExpressionValidator ID="regValSummary" runat="server"
    ControlToValidate="txtSummary" ErrorMessage="Invalid characters(&lt;&gt;&amp;#!) are not allowed" Text="*"
    ValidationExpression="[^&lt;&gt;&amp;#!]*" ValidationGroup="Valtxt">

</asp:RegularExpressionValidator>

<asp:RequiredFieldValidator ID="reqvalSummary" runat="server"
    ControlToValidate="txtSummary" ErrorMessage="Summary is required" Text="*"
    ValidationGroup="Valtxt">
</asp:RequiredFieldValidator>

Required field validator not working

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