golang基础-map

我的理解map就是Python中的字典。

转载请注明出处：http://www.cnblogs.com/SSSR/p/6351816.html

参考链接：http://studygolang.com/articles/3637

 

 

map.go

package learningmap

import "fmt"

type personInfo struct {
	ID      string
	Name    string
	Address string
}

func LearningMap() {
	
	//var numbers map[string]int
	var myMap map[string]personInfo
	
	rating := map[string]float32{"C": 5, "Go": 4.5, "Python": 4.5, "C++": 2}
	myMap = map[string]personInfo{"1234": personInfo{"1", "Jack", "Room 101,..."}}
	fmt.Println(rating["C"])
	fmt.Println(myMap["1234"])
	fmt.Println("ID:", myMap["1234"].ID)
	for key, value := range rating {
		fmt.Println("Key:", key, "Value:", value)
	}
}

func LearningMap1() {
	type personInfo struct {
	ID      string
	Name    string
	Address string
}
	 /*
    //声明一个map变量numbers,键名为string,值为int
    var numbers map[string] int
    //给map变量创建值,同时指定最多可以存储3个int值
    numbers = make(map[string] int, 3)
    //map元素赋值
    numbers["one"] = 1
    numbers["two"] = 2
    numbers["three"] = 3
    */

    //上面方式的简写方法
    numbers := map[string] int{
        "one": 1,
        "two": 2,
        "three": 3,
    }
    
    var myMap map[string] personInfo
    myMap = make(map[string] personInfo)
    myMap["persion1"] = personInfo{"1", "Amiee", "Street 101"}
    myMap["persion2"] = personInfo{"2", "Beva", "Street 102"}
    myMap["persion3"] = personInfo{"3", "Cencey", "Street 103"}
    
    /*
    // 上面方式的简写方法
    myMap := map[string] persionInfo{
        "persion1": personInfo{"1", "Amiee", "Street 101"},
        "persion2": personInfo{"2", "Beva", "Street 102"},
        "persion3": personInfo{"3", "Cencey", "Street 103"},
    }
    */
    
    //map元素打印
    fmt.Printf("%v\n", numbers)
    fmt.Println(numbers)
    fmt.Println(numbers["two"])

    fmt.Println(myMap)
    fmt.Println(myMap["persion1"])
    
    //map元素查找
    p1, ok := myMap["persion1"]
    if ok{
        fmt.Println("Found persion1, name", p1.Name, ", info", p1 )
    }else{
        fmt.Println("Not Found persion1")
    }
    
    //map元素修改
    //map是一种引用类型，如果两个map同时指向一个底层，那么一个改变，另一个也相应的改变。
    numbersTest := numbers
    numbersTest["one"] = 11
    fmt.Println(numbers)   

    //map元素删除
    delete(numbers, "one")
    fmt.Println(numbers)    
}

/*
   输出结果如下


[root@localhost mygo]# go run  test.go 
map[one:1 two:2 three:3]
map[one:1 two:2 three:3]
2
map[persion1:{1 Amiee Street 101} persion2:{2 Beva Street 102} persion3:{3 Cencey Street 103}]
{1 Amiee Street 101}
Found persion1, name Amiee , info {1 Amiee Street 101}
map[one:11 two:2 three:3]
map[two:2 three:3]
}
*/

　　map_test.go

package learningmap

import "fmt"
import "testing"

var print = fmt.Println

func TestLearningMap(t *testing.T) {
	LearningMap()
	print("这是一个测试！")
}


func TestLearningMap1(t *testing.T) {
	LearningMap1()
	print("这是一个测试！")
}