Jquery modal dialog not fire in image button click

Jquery modal dialog not fire in image button click

this is my code
$(function () {
var dialogshow = true;
if (dialogshow) {
$('#dialog').dialog({
autoOpen: false,
width: 600,
closeOnEscape: true,
resizable: false,
draggable: true,
modal: true,
title: 'Add New Project',
show: {
effect: 'blind',
duration: 1000
},
hide: {
effect: 'explore',
duration: 1000
}
});
}
});
$("#ImgProjAdd").click(function () {
$("#dialog").dialog("open");
return false;
});
<asp:ImageButton ID="ImgProjAdd" runat="server"
ImageUrl="~/images/plus2.png" />
I am new one to Jquery and am using asp.net master and content pages and
using datepicker that are working properly but modal dialog not working if
remove line auto open it is working fine but i need when image button
click modal dialog fire. please give me solution thanks to advance