using javascript how to validate controls

I write a Javascript in Html Page

function checkProjectSelected(ProjectID)

{ var projectname;

projectname = document.getElementById (ProjectID).value;

if (projectname ==0)

{ alert ("select Project Name");

return false; }

}

<asp:TemplateColumn>
<HeaderTemplate>
<asp:Label id="lblproject" Runat="server">Project</asp:Label>
</HeaderTemplate>
<ItemTemplate>
<asp:DropDownList id=ddlproject Runat="server" OnSelectedIndexChanged="ddlproject_OnSelectedIndexChanged" SelectedIndex='<%# DataBinder.Eval(Container.DataItem,"PK_PC_ID")%>'>
</asp:DropDownList>
<asp:RequiredFieldValidator ID="requiredFieldproject" Display="None" Runat="server" ControlToValidate="ddlproject"
InitialValue="0" ErrorMessage="Select Project Name"></asp:RequiredFieldValidator>
</ItemTemplate>
</asp:TemplateColumn>


Write a coding in pageloadevent

btnSubmit.Attributes.Add ("onclick","return checkProjectSelected('ddlproject');");



ddlproject is a dropdown list. This is not working properly. My code is correct or not. How to check the validation. Pls help me.

Thanks.
viveka

I think you are missing the form in document.getelementbyid

try using document.form1.control name.value.

And make sure the function is returning true if the value is selected for this u may add "return true;" in else condition.

HTH,

Amit

i write a code in datagrid _ ItemCommand
string ddlproject = ((DropDownList)e.Item .FindControl ("ddlproject")).ClientID ;
btnSubmit.Attributes.Add ("onClick","Javascript:return validateControls('ddlproject');");

It is working properly.

Thank You