Golang switch语句的具体使用

switch expression {
case value1:
    // 当 expression 的值等于 value1 时执行
case value2:
    // 当 expression 的值等于 value2 

switch x {
case 1:
    fmt.Println("x is 1")
    fallthrough
case 2:
    fmt.Println("x is 2")
    fallthrough
case 3:
    fmt.Println("x is 3")
default:
    fmt.Println("x is not 1, 2, or 3")
}

y := 20

switch {
case y > 10:
    fmt.Println("y is greater than 10")
case y == 10:
    fmt.Println("y is exactly 10")
default:
    fmt.Println("y is less than 10")
}

switch z := computeValue(); {
case z > 10:
    fmt.Println("z is greater than 10")
case z == 10:
    fmt.Println("z is exactly 10")
default:
    fmt.Println("z is less than 10")
}

var i interface{} = /* 一个值 */

switch t := i.(type) {
case string:
    fmt.Println("i is a string:", t)
case int:
    fmt.Println("i is an int:", t)
default:
    fmt.Printf("Unknown type %T\n", t)
}

switch x {
case 1, 2, 3:
    fmt.Println("x is 1, 2 or 3")
default:
    fmt.Println("x is not 1, 2, or 3")
}

switch {
case x > 0 && x < 10:
    fmt.Println("x is between 1 and 9")
case x == 10 || x == 20:
    fmt.Println("x is either 10 or 20")
}

switch {
case score >= 90:
    fmt.Println("Grade: A")
case score >= 80:
    fmt.Println("Grade: B")
case score >= 70:
    fmt.Println("Grade: C")
default:
    fmt.Println("Grade: F")
}

for {
    switch {
    case someCondition():
        fmt.Println("Condition met")
        break // 默认只会跳出 switch
    default:
        fmt.Println("Default case")
    }
    break // 退出 for 循环
}

for x := 0; x < 5; x++ {
    switch {
    case x%2 == 0:
        // 跳过偶数
        continue
    }
    fmt.Println("Odd:", x)
}