We can use thefind()method to find an object in an array of objects in JavaScript by its property value. Here, thefind()method returns the first array element provided that satisfies the given testing function. Any values that don’t fulfill the testing function will returnundefined. The below...
12.Array.filter() -+-对数组中的每个元素运行给定函数,返回该函数会返回 true 的元素组成的数组,传参和forEach一样:array.filter(function(currentValue,index,arr),thisValue) 1 2 3 4 5 letarr = [1, 2, 3, 4, 5] letbigNum = value => value > 3 letnewArr = arr.filter(bigNum) console.l...
// StringArray.from('abc');// ["a", "b", "c"]// SetArray.from(newSet(['abc','def']));// ["abc", "def"]// MapArray.from(newMap([[1,'abc'], [2,'def']]));// [[1,'abc'], [2,'def']]// 天生的类数组对象argumentsfunctionfn(){returnArray.from(arguments); }fn(...
Lovefield - Lovefield is a relational database for web apps, By Google. Dexie.js - Dexie.js is a wrapper library for indexedDB. proxy-web-storage - Keep the type of storage value unchanged and change array and object directly. Supports listening to the changes and setting expires. PostgreSQL...
constresult = array1.findIndex(findIndexCallback); console.log(result);// Output: 1 三、应用示例1:查找对象中符合条件的元素 在一个对象数组中,我们经常需要查找符合某个条件的对象。这时就可以使用findIndex()方法来实现。 constusers =[ {name:'John', age:25}, ...
eslint: object-shorthand // bad const atom = { value: 1, addValue: function (value) { return atom.value + value; }, }; // good const atom = { value: 1, addValue(value) { return atom.value + value; }, };3.4 Use property value shorthand. eslint: object-shorthand Why? It is...
fill() Fill the elements in an array with a static value filter() Creates a new array with every element in an array that pass a test find() Returns the value of the first element in an array that pass a test findIndex() Returns the index of the first element in an array that pas...
Array.from(obj, function(value, index){ console.log(value, index, this, arguments.length); return value.repeat(3); //必须指定返回值,否则返回 undefined }, obj); 结果如图: 以上结果表明,通过 Array.from 这个方法可以自定义加工函数的处理方式,从而返回想要得到的值;如果不确定返回值,则会返回 undefi...
Returns the element's top property value from the getBoundingClientRect method.JavaScript Copy window.scrollElementIntoView = (element) => { element.scrollIntoView(); return element.getBoundingClientRect().top; } Where IJSRuntime.InvokeAsync calls the JS function in component code, the ElementRe...
create function arrayContainsPropertyValue(items varchar(10000), str varchar(100), prop varchar(100)) returns tinyint language javascript as $$ const arr = JSON.parse(items) return arr.find((item) => item[prop] == str) != null