How to check undefined, empty and null in JavaScript/JQuery ?
If you are working on jquery and However you want to check variable is undefined or not then you can easily check by typeof operator, which is simple, fast and cross-platform:
if(typeof i == "undefined"){
alert('undefined');
}
If you are working on jquery and However you want to check variable is empty or not then you can easily check by compare with empty string:
if(i == ''){
alert('Empty');
}
If you are working on jquery and However you want to check variable is null or not then you can easily check by compare with "null":
if(i == null || i == NULL){
alert('null');
}
Try this......

Hardik Savani
My name is Hardik Savani. I'm a full-stack developer, entrepreneur and owner of Aatman Infotech. I live in India and I love to write tutorials and tips that can help to other artisan. I am a big fan of PHP, Javascript, JQuery, Laravel, Codeigniter, VueJS, AngularJS and Bootstrap from the early stage.
My name is Hardik Savani. I'm a full-stack developer, entrepreneur and owner of Aatman Infotech. I live in India and I love to write tutorials and tips that can help to other artisan. I am a big fan of PHP, Javascript, JQuery, Laravel, Codeigniter, VueJS, AngularJS and Bootstrap from the early stage.
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