check is null or undefined js code example
Example 1: javascript check if undefined or null
if( typeof myVar === 'undefined' || myVar === null ){
// myVar is undefined or null
}
Example 2: javascript check if object is null or empty
if (typeof value !== 'undefined' && value) {
//deal with value'
};
Example 3: javascript check if undefined or null or empty string
// simple check do the job
if (myString) {
// comes here either myString is not null,
// or myString is not undefined,
// or myString is not '' (empty).
}
Example 4: javascript check if undefined or null
// simple check do the job
if (myVar) {
// comes here either myVar is not null,
// or myVar is not undefined,
// or myVar is not '' (empty string).
}