c# - Ajax function to validate on click of a button: -

c# - Ajax function to validate on click of a button: -

in page have dropdown panel1 panel2 button move next onclick of dropdown info in panel1 displayed. , panel 2 displays selected data.

when there nil selected indropdown panel1 set invisible.

now want if there nil selected in dropdown.onclick of button alert message displayed 'please select info panel1 , move next' before had done using javascript function custom validation function on next button. want upgrade ajax.

javascript code:

function validate(sender, args) { if (document.getelementbyid("ctl00_rightcontainer_contenttable1_panel1").style.display == 'none') { args.isvalid = false; } else { args.isvalid = true; } }

after trying ajax function used visible property , error in javascript saying object not found since on load panel1 invisible. hav upgraded rest functions ajax dont knw hw shal this.

if ajax means asp.net update panel preet easy dont it.

put panel within updatepanels

dont forgot add together scriptmanager on top:

<asp:scriptmanager runat="server" id="sc1"/> <asp:updatepanel id="up1" runat="server"> </asp:updatepanel>

and dropdowns set autopostback true.

the dropdown have selectedindex , in selectedindex check validations , show next panel or message

you can show message this:

in label

or

alert or jquery popup

scriptmanager.registerstartupscript(this.page , typeof(page) , "alertv" , "alert('errors');" , true);

c# asp.net ajax asp.net-ajax