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Justin Rose
11,958 PointsNull and Undefined: Javascript issue: opening assignment
When following and starting the lesson, i downloaded the new files associated with the lesson and open my console after i drag the index.html file from the folder to the browser to open the url. The problem is when i refresh the page when i refresh the page i dont see anything in the console. I thought it was supposed to say " var myVar; undefined "i dont see this in the console is myscript.js connected?
any help would be appreciated
thank you
1 Answer

Robert Richey
Courses Plus Student 16,352 PointsWhen I downloaded the lesson files, all the code was already typed - and yes, the index.html file does have a link to myscript.js
Once the Web page is open, open the console by pressing F12. You should see true
true
If
all on separate lines.
When the page loads, here is the relevant JavaScript that produces that output:
var myVar;
// undefined = true;
console.log(typeof myVar === "undefined");
console.log(myVar === undefined);
var x = null;
if(myVar == null){
console.log("If");
} else {
console.log("Else");
}
After watching the video, everything seems to be in order.

Robert Richey
Courses Plus Student 16,352 PointsThe only thing you should see in the console is what gets passed into console.log()
.
// these are equality checks being passed into console.log()
// the result will print true or false to the console
console.log(typeof myVar === "undefined");
console.log(myVar === undefined);
Robert Richey
Courses Plus Student 16,352 PointsRobert Richey
Courses Plus Student 16,352 PointsHi Justin,
Edit: I just found it. I'll post again when I have a better understanding of the problem and solution.
Can you please post a link to the lesson and I'll check it out?