constarray=[3,8,12,6,10,2];// Find 10 in the given array.functioncheckForN(arr,n){for(leti=0;i<array.length;i++){if(n===array[i]){return`${true}${n}exists at index${i}`;}}return`${false}${n}does not exist in the given array.`;}checkForN(array,10); 这就是线性搜索...
AI代码解释 object.runsOnlyIfMethodExists?.() 例如下面的parent对象,如果我们直接调用parent.getTitle(), 则会报Uncaught TypeError: parent.getTitle is not a function错误,parent.getTitle?.()则会终止不会执行 代码语言:javascript 代码运行次数:0 运行 AI代码解释 letparent={name:"parent",friends:["p1",...
functionhasEvent(element,eventName){consteventListeners=getEventListeners(element);returneventListeners&&eventListeners[eventName].length>0;}constbutton=document.querySelector('#myButton');console.log(hasEvent(button,'click'));// trueconsole.log(hasEvent(button,'mouseover'));// false 1. 2. 3. ...
Object.hasOwn(object,'age')// trueletobject2 =Object.create({age:24})Object.hasOwn(object2,'age')// false The 'age' attribute exists on the prototypeletobject3 =Object.create(null)Object.hasOwn(object3,'age')// false an...
if (element) { const rawText = element.GetText(); //gets the text from a particular element element.Delete(); //delete the content const wordToFind = "apple"; // Replace "apple" with the word you want to find const replacementWord = "banana"; // Replace "banana" with the word yo...
PRAGMA foreign_keys=false;-- --- Table structure for sys_user-- ---DROPTABLEIFEXISTS"sys_user";CREATETABLE"sys_user" ( "id"bigint(11)NOTNULL, "role_id"bigint(11)NOTNULL, "user_name"varchar(255)NOTNULL, "user_pass"varchar(64)NOTNULL, "nick_name"...
key: It is the key of the element of the map which has to be searched. 返回值: The Map.has() method returns a boolean value. It returns true if the element exists in the map else it returns false if the element doesn’t exist. ...
#Array.push() Element if does not exist using Array.find() This is a three-step process: Use theArray.find()method to iterate over the array. On each iteration, check if the specified value exists in the array. If theArray.find()method returnsundefined, push the value into the array....
If the value exists, then the function will return the index value of the element, else it will return -1 Syntax 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', '...
Object.hasOwn(object,'age')// trueletobject2 =Object.create({age:24})Object.hasOwn(object2,'age')// false The 'age' attribute exists on the prototypeletobject3 =Object.create(null)Object.hasOwn(object3,'age')// false an object that does not inherit from "Object.prototype" ...