const fruits = ["Banana", "Orange", "Apple", "Mango"]; fruits.includes("Mango"); check if an item exists in an array: const nums = [ 1, 3, 5, 7]; console.log(nums.includes(3)); // true
//code to check if a value exists in an array using javascript for loop var fruits_arr = ['Apple', 'Mango', 'Grapes', 'Orange', 'Fig', 'Cherry']; function checkValue(value, arr) { var status = 'Not exist'; for (var i = 0; i < arr.length; i++) { var name = arr[...
varfruits=["Apple","Banana","Mango","Orange","Papaya"];// Check if a value exists in the fruits arrayif(fruits.indexOf("Mango")!==-1){alert("Value exists!")}else{alert("Value does not exists!")} ES6 has introduced theincludes()method to perform this task very easily. But, ...
Add value if not exists Loop through the array to check whether a particular username value already exists and if it does do nothing, but if it doesn’t add a new object to the array. const arr = [{ id: 1, username: 'fred' }, { id: 2, username: 'bill' }, { id: 3,...
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...
} /** * 网络信息获取 * @param requestParam */ function intenetInfo(requestParam){ requestParam['macAddr'] = returnCitySN["cname"]; requestParam['ipAddr'] = returnCitySN["cip"]; return requestParam; } //检查是否安装了某插件,如果安装了返回版本号 function checkePlugs(pluginname) { var f ...
5.`arrayToHtmlList`:数组转`li`列表 此代码段将数组的元素转换为标签,并将其附加到给定ID的列表中。 代码语言:javascript 复制 constarrayToHtmlList=(arr,listID)=>(el=>((el=document.querySelector('#'+listID)),(el.innerHTML+=arr.map(item=>`${item}`).join('')))();arrayToHtmlList(['...
JavaScript Array: Exercise-1 with Solution Check Array Input Write a JavaScript function to check whether an 'input' is an array or not. Test Data: console.log(is_array('w3resource')); console.log(is_array([1, 2, 4, 0]));
Array.prototype.hasObjectExists =function(item) {for(i = 0; i < this.length; i++) {if(this[i].id == item.id){returntrue; }//www.java2s.com}returnfalse; }; PreviousNext Related Javascript Array hashCode() Javascript Array hasItem(item) ...
In this post, we will explore various ways to find a particular object in a JavaScript array. Let us assume that we have an array as shown in the listing below and we need to find whether an object with an id of ‘4’ exists: ...