SCARD

SCARD

获取集合的成员数。如果key不存在，返回0.

Command

$ redis-cli.exe -h 127.0.0.1 -p 6379
127.0.0.1:6379> sadd s1 1 2
(integer) 2
127.0.0.1:6379> scard s1
(integer) 2
127.0.0.1:6379> scard fakeSet
(integer) 0

Code

func scard(c redis.Conn) {
    defer c.Do("DEL", "s1")
    c.Do("SADD", "s1", 1, 2)
    memberCount, err := c.Do("SCARD", "s1")
    if err != nil {
        colorlog.Error(err.Error())
        return
    }
    fmt.Println("The number of members is:", memberCount)
    //  If key doesn't exist, will return 0
    memberCount, err = c.Do("SCARD", "fakeSet")
    if err != nil {
        colorlog.Error(err.Error())
        return
    }
    fmt.Println("The number of members of fakeSet is:", memberCount)
}

Output

$ go run main.go 
The number of members is: 2
The number of members of fakeSet is: 0