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 any...

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 parameter to a f...

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 any...

PHP with HTML textarea?

I am quite new to PHP/HTML all this kind of stuff so sorry if this is an easy question! Is there a way to read the ...

How can I print variable and string on same line in Python??

I am using python to work out how many children would be born in 5 years if a child was born every 7 seconds. The pr...

How to check if type of a variable is string??

Is there a way to check if the type of a variable in python is a string, like: isinstance(x,int); for integer val...

How can I simulate an array variable in MySQL??

It appears that MySQL doesn't have array variables. What should I use instead? There seem to be two alternatives...

Declaring & Setting Variables in a Select Statement?

I'm attempting to write a simple query where I declare some variables and then use them in a select statement in Ora...

How do you know a variable type in java??

Let's say I declare a variable: String a = "test"; And I want to know what type it is, i.e., the output should be...

What is the use of a private static variable in Java??

If a variable is declared as public static varName;, then I can access it from anywhere as ClassName.varName. I am a...

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 parameter to a f...

How do I pass JavaScript variables to PHP??

I want to pass JavaScript variables to PHP using a hidden input in a form. But I can't get the value of $_POST['hid...

Best way to retrieve variable values from a text file??

Referring on this question, I have a similar -but not the same- problem.. On my way, I'll have some text file, stru...

how to use a variable from a superclass to a subclass??

I have a superclass and I want to use a variable that is inside this superclass into my subclass. How can this be po...