Dropdownlist Validation with RequiredFieldValidator

Vishwakant Tripathi

I have one Dropdownlist to be validated by RequiredFieldValidator. And It has OnSelectedIndexChanged event so I have set AutoPostBack=true.(That is required because this dropdownlist will fill another dropdownlist on selection index changed).
I have set InitialValue="-1" that is first item as "--Select--". As I click on submit button it reload the page and then it shows error message.

This is my controls....

Is there any option that can be used to validate dropdownlist without reloading page.

Thanks.

Vishwakant.

6 Replies

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Bikesh Srivastava10y ago
Visit here you can find proper solution...
http://asp.net-tutorials.com/validation/required-field-validator/
Vinay Singh10y ago
Hi
check the link
http://www.aspdotnet-pools.com/2015/06/validate-dropdownlist-using.html
Rajeesh Menoth10y ago
Hi Vd Tripathi,

Add group name in "RequiredFieldValidator" and "Asp :Button "

Try this code :
<asp:DropDownList ID="ddlMsgSubCategories" runat="server" Width="320px" ValidationGroup="drop"AutoPostBack="True" CausesValidation="True" OnSelectedIndexChanged="ddlMsgSubCategories_SelectedIndexChanged" CssClass="fontStandardInput">asp:DropDownList><br />

<asp:RequiredFieldValidator runat="server" ID="rfvMsgSubCategories" ValidationGroup="drop" ControlToValidate="ddlMsgSubCategories" Display="Dynamic" CssClass="fontValidation" InitialValue="-1" SetFocusOnError="true">asp:RequiredFieldValidator>
Reference :

http://stackoverflow.com/questions/5310609/dropdownlist-validation-in-asp-net-using-required-field-validator
Midhun Tp10y ago
Hi,
It is working fine for me. Have you given value for "--Select--" in dropdown as -1?
Vishwakant Tripathi10y ago
I get error message, but I debug and got it goes first on page load, thenSubmit button's click event in code behind, and then it come back to page and shows error message. So i am looking if any other way to avoid page loading and submit button's server side code.

And first item be default will be selected that is "--Select--".
Midhun Tp10y ago
Hi,
Above code is working fine with me. The button click is not firing if we haven't selected any option from dropdown. Are you not getting error message even though the dropdown is not selected?