public createMouse(){this.mouseView =newMouse();//定义二维数组for(vari = 0;i < 3;i++){this.mouseArray[i] =[]; }this.mouseArray.push([]);for(vari = 0;i < 3;i++){for(varj = 0;j <= 3; j++) {this.mouseArray[i][j] =this.mouseView.createMouse(300*j,300*i);this.ad...
function create2DArray(rows: number, cols: number, initialValue: any): any[][] { let arr: any[][] = new Array(rows); for (let i = 0; i < rows; i++) { arr[i] = new Array(cols).fill(initialValue); } return arr; } let myArray: number[][] = create2DArray(3, 3, 0)...
// 第二个是一个简单类型数据,返回重复 N 次的指定类型数组 type CreateArrayType<T> = (x:number, y:T) => T[]; const createArray2:CreateArrayType<number> = (x, y) => { let result = []; for(let i=0; i<x; i++){ result[i] = y; } return result; } createArray2(2, 2)...
const arr1 = createArray(11, 3); const arr2 = createArray("aa", 3); console.log(arr1[0].toFixed(), arr2[0].split("")); 2. 使用函数泛型 function createArray2<T>(value: T, count: number) { const arr: Array<T> = []; for (let index = 0; index < count; index++) { ...
return Array(padding + 1).join(" ") + value; } if (typeof padding === "string") { return padding + value; } throw new Error(`Expected string or number, got '${padding}'.`); } typeof类型保护只支持两种形式:typeof v === "typename"和typeof v !== typename,"typename"必须是"nu...
myArray[index] = updatedValue myArray.with(index, updatedValue) Note that the copying methods always create a new array, whereas the mutating operations are inconsistent. These methods aren’t just available on plain Arrays– they’re also available on TypedArrays like Int32Array, Uint8Array, ...
functiontriple(input:number|string):number|string{if(typeofinput==='number'){returninput*3;}else{return(newArray(4)).join(input);}} TypeScript 能否正确推断出各个逻辑分支中的input类型呢?借助基于控制流的类型分析(Control Flow Based Type Analysis)以及typeof等类型哨兵(Type Guard),TypeScript 可以成...
interfacequeueInterface<Type>{enQueue(dataItem:Type):void;deQueue():Type|undefined;isEmpty():boolean;isFull():boolean;size():number;printQueue():void;}classQueueClass<Type>implementsqueueInterface<Type>{privateQueueData:Array<Type>=[];privatemaxSize:number=0;constructor(length:number){this.maxSize=...
type LowercaseGreeting = "hello, world"; type Greeting = Capitalize<LowercaseGreeting>; // 相当于 type Greeting = "Hello, world" Uncapitalize<StringType>:将字符串首字母转为小写格式 type UppercaseGreeting = "HELLO WORLD"; type UncomfortableGreeting = Uncapitalize<UppercaseGreeting>; // 相当于 typ...
createA3<N, T> { (a: N, b: T): Array<T>; } let func4: createA3<number, string>; func4 = function (i, s) { let arr: string[] = []; arr[i] = s; return arr; }; func4(1, "dqwy"); //泛型约束 interface Length4 { length: number; } interface createA4<N, T ...