javascript if undefined
if(typeof comment === 'undefined') {
alert('Variable "comment" is undefined.');
} else if(comment === null){
alert('Variable "comment" is null.');
}javascript if undefined
if(typeof comment === 'undefined') {
alert('Variable "comment" is undefined.');
} else if(comment === null){
alert('Variable "comment" is null.');
}javascript check if null
if (variable === null) { //Executes only if variable is null but not undefined
//Code here
}
if (variable == null) { //Executes if variable is null OR undefined
//Code here
}Copyright © 2021 Codeinu
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