Javascript: How to check if a string is empty?
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What is the best way to check for an empty string in JavaScript?
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?
我检查长度。
if (str.length == 0) {
}
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.
这应该工作：
if (variable === "") {
}