variables Archives - Page 15 of 16

How to check if a variable is set in Bash

How do I know if a variable is set in Bash? For example, how do I check if the user gave the first ...

April 10, 2022
0 Comments

What is the scope of variables in JavaScript?

What is the scope of variables in javascript? Do they have the same scope inside as opposed to outside a function? Or does ...

April 10, 2022
0 Comments

JavaScript check if variable exists (is defined/initialized)

Which method of checking if a variable has been initialized is better/correct? (Assuming the variable could hold anything (string, int, object, function, etc.)) ...

April 10, 2022
0 Comments

How can I determine if a variable is ‘undefined’ or ‘null’?

How do I determine if variable is undefined or null? My code is as follows: var EmpName = $("div#esd-names div#name").attr('class'); if(EmpName == 'undefined'){ ...

April 10, 2022
0 Comments

How do JavaScript closures work?

This question’s answers are a community effort. Edit existing answers to improve this post. It is not currently accepting new answers or interactions. ...

April 9, 2022
0 Comments

Java: “error: cannot find symbol”

April 8, 2022
0 Comments

Non-static variable cannot be referenced from a static context

You must understand the difference between a class and an instance of that class. If you see a car on the street, you ...

April 8, 2022
0 Comments

“No X11 DISPLAY variable” – what does it mean?

If you’re on the main display, then or if you’re using csh or tcsh before running your app. Actually, I’m surprised it isn’t ...

April 7, 2022
0 Comments

What is the difference between a local variable, an instance field, an input parameter, and a class field?

A local variable is defined within the scope of a block. It cannot be used outside of that block. Example: if(x > 10) { String ...

April 6, 2022
0 Comments