Use the strict equality operator (===) to check if the string is empty in JavaScript. This is because === will only return true if the values on both sides are of the same type, in this case, a string.
if(variable === "") {
}Use !value. It works for undefined, null and even '' value:
Note: (false == “”) will return true, and (false === “”) will return false.
JavaScript checks if the string is empty
A simple example code check string is empty using the if condition statement.
<!DOCTYPE html>
<html>
<body>
<script>
var day = "";
if (day === "") {
console.log("String is empty")
}
</script>
</body>
</html> Output:
But for a better check null also.
if(str === null || str === '')
{
//enter code here
}Do comment if you have any doubts or suggestions on this JS string empty topic.
Note: The All JS Examples codes are tested on the Firefox browser and the Chrome browser.
OS: Windows 10
Code: HTML 5 Version