You can use theindexOf()method to check whether a given value or element exists in an array or not. TheindexOf()method returns the index of the element inside the array if it is found, and returns -1 if it not found. Let's take a look at the following example: ...
<!DOCTYPE html> check if a value exists in an array var progLang = ["C", "Java", "C++", "Python", "PHP"]; if(progLang.indexOf("Java") !== -1){ console.log("Element exists"); }else{ console.log("Element does not exist"); } OutputElement existsUsing includes...
If the value exists, then the function will return the index value of the element, else it will return -1Syntax put-array-or-string-here.indexOf() Code //code to check if a value exists in an array using javascript indexOf var fruits_arr = ['Apple', 'Mango', 'Grapes', 'Orange'...
In JavaScript, you can check if every element of the first array exists in the second array, in the following ways: Using Array.prototype.every();
if(document.querySelector(".elementClass")) {// The element exists}else{// The element does not exist} Check if an element exists in JavaScript Below is a JavaScript example to show the use ofdocument.querySelector()to check if a specific element exists. ...
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let user = { name: 'John Doe', age: 17, profession: 'Farmer' }; // Check if key exists let hasKey = user.hasOwnProperty('name'); if (hasKey) { console.log('This key exists.'); } else { console.log('This key does not exist.'); } Checking an Array You might begin to...
使用jQuery 的$.inArray()方法: 代码语言:javascript 复制 constarray=[1,2,3,4,5];constvalueToCheck=3;if($.inArray(valueToCheck,array)!==-1){console.log("Value exists in array.");}else{console.log("Value does not exist in array.");} ...
vara = ["Abhishek","Biraj","Mahi","Tamana","Sahir"];// This will check if the given value exists in the "a" arrayif(a.indexOf("Sahir") !== -1){alert("The value is present in the array.!") }else{alert("The value is not present in the array.!") ...
Check if cookies are enabled/disabled in a browser Check If Session Exists Check whether protocol handler installed or not Check, Uncheck the CheckBoxes of repeater using JavaScript Checkbox not showing check mark when checked property set through javascript CheckBox text align horizontally middle CheckB...