check if a value exist in an array javascript code example
Example 1: javascript method to see if item exists in array
var fruits = ["Apple", "Banana", "Mango", "Orange", "Papaya"];
if(fruits.indexOf("Mango") !== -1){
alert("Value exists!")
} else{
alert("Value does not exists!")
}
Example 2: check value exist in array javascript
[1, 2, 3].includes(2);
[1, 2, 3].includes(4);
[1, 2, 3].includes(1, 2);
Example 3: javascript check if in array
var extensions = ["image/jpeg","image/png","image/gif"];
if(extensions.indexOf("myfiletype") === -1){
alert("Image must be .png, .jpg or .gif");
}