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// simple check do the job
if (myString) {
// comes here either myString is not null,
// or myString is not undefined,
// or myString is not '' (empty).
}
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if( typeof myVar === 'undefined' || myVar === null ){
// myVar is undefined or null
}
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let myStr = null;
if (myStr === null || myStr.trim() === "") {
console.log("This is an empty string!");
} else {
console.log("This is not an empty string!");
}
/*
This will return:
"This is an empty string!"
*/
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if (typeof value !== 'undefined' && value) {
//deal with value'
};
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function isNullOrEmpty(str) {
return str === null || str.trim() === '';
}
// Usage example
const myString = null;
const result = isNullOrEmpty(myString);
console.log(result); // Output: true
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let myStr = null;
if (myStr === null || myStr.trim() === "") {
console.log("This is an empty string!");
} else {
console.log("This is not an empty string!");
}
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if( value ) {
//
}
/**
* This will evaluate to true if value is not:
* null
* undefined
* NaN
* empty string ("")
* 0
* false
*/
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var string = "not empty";
if(string == ""){
console.log("Please Add");
}
else{
console.log("You can pass"); // console will log this msg because our string is not empty
}
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Use for Empty string, undefined, null,
//To check for a truthy value:
if (strValue) {
// strValue was non-empty string, true, 42, Infinity, [], ...
}
//To check for a falsy value:
if (!strValue) {
// strValue was empty string, false, 0, null, undefined, ...
}