查看生成的 JS 代码,可以看 到TypeScript 编译器生成了一个传统的基于索引的for循环来遍历数组: 代码语言:javascript 代码运行次数:0 运行 AI代码解释 varnumbers=[4,8,15,16,23,42];for(var_i=0,numbers_1=numbers;_i<numbers_1.length;_i++){varnumber=numbers_1[_i];console.log(number);} 如果运...
System.arraycopy(es, i + 1, es, i, newSize - i); es[size = newSize] = null; } 1. 2. 3. 4. 5. 6. 7. 8. 我们发现每调用一次remove()方法,modCount就会自增,而expectedModCount 默认和modCount相等,当modCount自增加1,而expectedModCount 没有增加,就会抛出异常,这也就是foreach遍历时抛...
sanitizenumberArray(checker.numbers)) { return false; } return true; } function sanitizenumberArray(checker: any) { if (!Array.isArray(checker)) { return false; } for (let i = 0; i < checker.length; i++) { if (typeof checker[i] != "number") { return false; } } return true...
// ES5:var name = 'Semlinker'; 2.4 Array 类型 let list: number[] = [1, 2, 3]; // ES5:var list = [1,2,3]; let list: Array<number> = [1, 2, 3]; // Array<number>泛型语法 // ES5:var list = [1,2,3]; 2.5 Enum 类型 使用枚举我们可以定义一些带名字的常量。 使用枚举可...
functionfn1(){return[Promise.resolve(1),Promise.resolve(2)];}functionfn2(){return[1,2];} 在这里顺带一提,对Array.map的每一项进行异步等待的方法: 代码语言:javascript 代码运行次数:0 运行 AI代码解释 awaitPromise.all(arr.map(asyncitem=>{returnawait...
function pickCard(x): any {//Check to see if we're working with an object/array//if so, they gave us the deck and we'll pick the cardif(typeofx =="object") { let pickedCard= Math.floor(Math.random() *x.length);returnpickedCard; ...
case Array.isArray(x): // 'x' is a 'string | any[]' here. console.log(x.length); // falls through... default: // 'x' is 'unknown' here. // ... } } This feature was spearheaded initial work by Mateusz Burzyński We’d like to extend a "thank you!" for this contributio...
include- Array of.tsfiles to compile. You can also use glob patterns such as"src/**/*". Note Compile If you are using a TypeScript-enabled framework then the types will automatically be compiled when you build the app. If you are using TypeScript with the APIs AMD CDN modules in a ...
isArray(x): // 'x' is 'unknown' here. console.log(x.length); default: // 'x' is 'unknown' here. } } 此前这种写法内,各个 case 语句的 x 不会正常进行类型收窄,如 typeof x === "string" 成立时 x 应被收窄到 string 类型这样,5.3 版本已对此问题进行了修正。 布尔值比较 此前...
enabling richer type checking for better error reporting and tools. For example, generics allow the typing of the Array#map function from JavaScript to relate the element type of the array with the parameter to the callback function (‘T’ below), and the return type of the callback function...