我们如果想要获取某个map的值怎么做呢?

package main

import "fmt"

func main() {

    m := map[string]int{
        "a": 1,
        "b": 2,
        "c": 3,
    }

    fmt.Println("Geting values")
    courseName := m["a"]
}
key

例如:

package main

import "fmt"

func main() {

    m := map[string]int{
        "a": 1,
        "b": 2,
        "c": 3,
    }

    fmt.Println("Geting values")
    courseName := m["d"]
}

输出结果会为空字串. 我们怎么防止空字串的问题呢?

package main

import "fmt"

func main() {

    m := map[string]int{
        "a": 1,
        "b": 2,
        "c": 3,
    }

    fmt.Println("Geting values")
    courseName, ok := m["a"]
    fmt.Println(courseName,ok)
    if courseName, ok := m["d"]; ok{
        fmt.Println(courseName)
    }else{
        fmt.Println("key does not exist")
    }
}
boolean

file

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by JeffreyBool blog :point_right: link