Javascript: How to check if a string is empty? [duplicate]

I know this is really basic, but I am new to javascript and can't find an answer anywhere.

How can I check if a string is empty?

Solution 1:

I check length.

if (str.length == 0) {
}

Solution 2:

If you want to know if it's an empty string use === instead of ==.

if(variable === "") {
}

This is because === will only return true if the values on both sides are of the same type, in this case a string.

for example: (false == "") will return true, and (false === "") will return false.

Solution 3:

This should work:

if (variable === "") {

}

Solution 4:

But for a better check:

if(str === null || str === '')
{
    //enter code here
}