__doPostBack is not defined

Question

Im getting that error when try to call a __doPostBack on one of my pages, every page that i have in the project use __doPostBack function but in this particular page im gett

Answer 1

If the page doesn't have a control that causes a postback, __doPostBack() won't be output as a function definition. One way to override this is to include this line in your Page_PreRender():

this.Page.ClientScript.GetPostBackEventReference(, string.Empty);

This function returns a string calling __doPostBack(); but also forces the page to output the __doPostBack() function definition.