when use Asp.net net Url ReWriting Ajax WebMethod wont Called

Hi,m getting url like 
http://localhost:10869/Customer
$.ajax({ type: "POST", contentType: "application/json", data: "{'Type':'" + type + "'}", url: "CustomerMaster.aspx/getSelectList",//when m using Asp.Net Url Re-writing WebMethod wont called dataType: "json", success: function (data) {
} }); 
webMethod
public static string(string Type)
{
return "";
}

Thank You