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Other than creating a function, is there a shorter way to check if a value is undefined,null or false only in JavaScript?
The below if statement is equivalent to if(val===null && val===undefined val===false) The code works fine, I'm looking for a shorter equivalent.
if(val==null || val===false){ ; } Above val==null evaluates to true both when val=undefined or val=null.
I was thinking maybe using bitwise operators, or some other trickery.
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To check if a variable is equal to null or undefined , use the loose equality (==) operator. For example, age == null returns true if the variable age is null or undefined .
Answer: Use the equality operator ( == ) Therefore, if you try to display the value of such variable, the word "undefined" will be displayed. Whereas, the null is a special assignment value, which can be assigned to a variable as a representation of no value.
Finally, the standard way to check for null and undefined is to compare the variable with null or undefined using the equality operator ( == ). This would work since null == undefined is true in JavaScript. That's all about checking if a variable is null or undefined in JavaScript.
The undefined value is a primitive value used when a variable has not been assigned a value. The null value is a primitive value that represents the null, empty, or non-existent reference. When you declare a variable through var and do not give it a value, it will have the value undefined.
Well, you can always "give up" :)
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