Dropdownlist Validation with RequiredFieldValidator

Question

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.

Bikesh Srivastava · Answer

Visit here you can find proper solution... http://asp.net-tutorials.com/validation/required-field-validator/

Vinay Singh · Answer

Hi check the link http://www.aspdotnet-pools.com/2015/06/validate-dropdownlist-using.html

Rajeesh Menoth · Answer

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 T P · Answer

Hi It is working fine for me. Have you given value for --Select-- in dropdown as -1?

Vd Tripathi · Answer

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 T P · Answer

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?