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if(Array.isArray(myVarToTest)) {
// myVatToTest is an array
} else {
// myVarToTest is not an array
}
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let names=['Jhon','David','Mark'];
console.log(Array.isArray(names));
// true
let user={id:1,name:'David'};
console.log(Array.isArray(user));
// false
let age 18;
console.log(Array.isArray(age));
// false
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var colors=["red","green","blue"];
if(Array.isArray(colors)){
//colors is an array
}
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Array.isArray([]) //true
Array.isArray({}) //false
Array.isArray('') //false
Array.isArray(null) //false
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// Check if something is an Array
// just like you do with "typeof"
Array.isArray([1, 2, 3]); // true
Array.isArray('asdf'); // false
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var extensions = ["image/jpeg","image/png","image/gif"];
if(extensions.indexOf("myfiletype") === -1){
alert("Image must be .png, .jpg or .gif");
}
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let variable1 = [2, 3]
let variable2 = "test";
variable1.constructor === Array; // true
variable2.constructor === Array; // false