TypeScript学习笔记

# 变量声明
let msg: string = 'douzi'
console.log(msg)
let num: number = 20
console.log(num)
let end: boolean = true
console.log("end=" + end)
let a: any = 10
a = 'douzi'
console.log(a)
let p = {name:"douzi",age:20}
console.log(p.name)
console.log("age=" + p['age'])
let names: Array<string> = ["douzi","douzi1"]
console.log(names[0])
let ages: number[] = [20,21]
console.log("age1=" + ages[1])

# 条件语法
if(num % 2 == 0) {
    console.log("num 是偶数")
}else {
    console.log("num 是奇数")
}

if (num > 0) {
    console.log("num 是正数")
}else if(num < 0){
    console.log("num 是负数")
} else {
    console.log("num 是0")
}

# switch 
switch(msg) {
    case 'douzi': {
        console.log("douzi")
        break
    }
    case 'douzi1': {
        console.log("douzi1")
        break
    }
    default: {
        console.log('douzi2')
        break
    }
}

# 循环语法
for(let i = 0; i < 10; i++) {
    console.log("for i=" + i)
}

let i = 0;
while(i < 10) {
    console.log('while i=' + i ++)
}