let map1 = new Map(); map1.set('info', {name: 'Jack', age: "26"}); // access the elements of a Map console.log(map1.get('info')); // {name: "Jack", age: "26"} 1. 2. 3. 4. 5. 检查Map 元素 您可以使用 has() 方法检查元素是否在 Map 中。例如, con...
let map = new Map([["k1", "v1"], ["k2", "v2"], ["k3", "v3"]]); console.log(map instanceof Map); // true console.log(map); // Map(3) {"k1" => "v1", "k2" => "v2", "k3" => "v3"} </script> 1. 2. 3. 4. 5. 6. 7. 8. 9. 10. 11. 对于键是对...
// Such an array can be in one of two modes: // - fast, backing storage is a FixedArray and length <= elements.length(); // Please note: push and pop can be used to grow and shrink the array. // - slow, backing storage is a HashTable with numbers as keys. class JSArray: ...
map()does not change the original array. Array Iteration Methods: The Array entries() Method The Array every() Method The Array filter() Method The Array forEach() Method The Array keys() Method The Array map() Method Syntax array.map(function(currentValue, index, arr), thisValue) ...
_data.map(function(item) {let_columns =camelArr(item.columns); item.values.map(function(values) { _res.push(ArraytoObj(_columns, values)); }); });return_res; };</script></body></html> 出处:https://www.cnblogs.com/lixingwu/p/10236640.html ...
克隆 map 就像将Map.entries()转换成数组一样简单: 代码语言:javascript 代码运行次数:0 运行 AI代码解释 // `clone` is now a separate map that contains the same keys/values// as `map`.constclone=newMap(Array.from(map.entries)); 扩展
Being able to use objects as keys is an important Map feature. Example // Create Objects constapples = {name:'Apples'}; constbananas = {name:'Bananas'}; constoranges = {name:'Oranges'}; // Create a Map constfruits =newMap(); ...
graphics GraphicsLayer Provides access to the Map's GraphicsLayer. graphicsLayerIds String[] An array of the current GraphicsLayers in the map. height Number Current height of the map in screen pixels. id String Reference to HTML DIV or other element where the map is placed on the page. in...
An array of tile servers used for changing map tiles. TileLayer title String|null|undefined The title of the layer used to identify it in places such as the Legend and LayerList widgets. TileLayer type String For TileLayer the type is always "tile". TileLayer url String|null|undefined The...
filter(predicate: ArrayFunc<T, boolean>): DataArray<T>; map<U>(f: ArrayFunc<T, U>): DataArray<U>; flatMap<U>(f: ArrayFunc<T, U[]>): DataArray<U>; mutate(f: ArrayFunc<T, any>): DataArray<any>; limit(count: number): DataArray<T>; ...