yes course why is my course coming up as undefined?

Why does JavaScript return undefined when a variable is not initialized?

Jun 01, 2017 · This will mean that getRestaurantsByLocation is only called once the data has come back from the server. You could, of course, still store the lat and long in state if you want to and then call the callback but I think it's clearer to pass through the data it needs explicitly. ... of course, still store the lat and long in state if you want to ...

When do you get an undefined error when accessing an object?

Hi there! I seem to be having problems with the reporting on a course I have recently built, as when I go to review the questions I have answered on my LMS they all appear as "undefined". All my questions and feed back are named. Ive tested it as a questions bank as well as listed in their own scene. I've have done this in the past and not had ...

Why won't my course launch?

May 29, 2008 · Obviously your problem was with the missinterpretation of the DOM. getElementById is giving you the textbox, so .value gives you the text. So, ztb1 is the actual text. In the alert you're calling a value property of a string, which is …

How to return an undefined string for an undefined value?

Aug 02, 2020 · Fortunately, JavaScript offers a bunch of ways to determine if the object has a specific property: obj.prop !== undefined: compare against undefined directly. typeof obj.prop !== 'undefined': verify the property value type. obj.hasOwnProperty ('prop'): verify whether the object has an own property.

Question

I have a masterpage so in the content page I want to check for empty textboxes b4 the user submits. My code of "document.getElementById ( 'ctl00_ContentPlaceHolder1_TextBox1') keeps returing "undefined". Any ideas?

Answers

You're setting ztb1 to the value of the textbox, and then trying to get the value of the value! So, update your code to either this:

All replies

Check the html source and see if a control with this id 'ctl00_ContentPlaceHolder1_TextBox1' exists in your page