/*在进行类型检查时,请考虑'null'和'undefined'——null类型检测,const teacher: string = null;会报错*/// "strictFunctionTypes": true, /*分配函数时,请检查以确保参数和返回值与子类型兼容——对函数参数进行严格逆变比较*/// "strictBindCallApply": true, /*检查'bin
// src/example.ts /** * 这是一个用于演示的类 */ class ExampleClass { /** * 这是一个用于演示的方法 * @param name - 姓名 * @param age - 年龄 * @returns 返回一个字符串,表示问候语和年龄 */ sayHello(name: string, age: number): string { return `Hello, ${name}! You are ${ag...
radius ** 2; } else { // We know we're left with a square here! return shape.sideLength ** 2; } } 不仅是单一的判断,Typescript 4.4 还支持复合类型推导: 代码语言:javascript 代码运行次数:0 运行 AI代码解释 function doSomeChecks( inputA: string | undefined, inputB: string | undefined...
[optName:`data-${string}`]:unknown;}letb:OptionsWithDataProps={width:100,height:100,"data-blah":true,// 成功了!"unknown-property":true,// 错误!'unknown
type C = { a: string, b?: number } function f({ a, b }: C): void { // ... } 但是,通常情况下更多的是指定默认值,解构默认值有些棘手。首先,你需要在默认值之前设置其格式。 function f({ a, b } = { a: "", b: 0 }): void { // ... } f(); // ok, default to {...
TypeScript now reduces intersections with type variables and primitives more aggressively, depending on how the type variable’s constraint overlaps with those primitives. Copy declarefunctionintersect<T, U>(x: T, y: U): T & U; function foo<T extends"abc"|"def">(x: T, str:string,num: ...
Aliases and Interfaces allows types to be easily shared between different variables/objects.Type AliasesType Aliases allow defining types with a custom name (an Alias).Type Aliases can be used for primitives like string or more complex types such as objects and arrays:ExampleGet your own Type...
“Control character in string: {a}.” : “在字符串中出现了Control的字符”, “Avoid \\’.” : “避免 \\”, “Avoid \\v.” : “避免 \\v”, “Avoid \\x-.” : “避免 \\x-”, “Bad escapement.” : “错误的转义字符”, ...
(public firstName: string, public middleInitial: string, public lastName: string) { this.fullName = firstName + " " + middleInitial + " " + lastName; } } interface Person { firstName: string; lastName: string; } function greeter(person: Person) { return "Hello, " + person.first...
interfaceCanCheck{checkThing:(x:string)=>boolean;} and implement it with an object: constobj={checkThing:(sn:string|number)=>{returntrue;}}objsatisfiesCanCheck;// OK A common confusion is to say that sincestring | numberis a bigger type thanstring, this program should be rejected, since...