zrank

1. 基本語法

zrank(key, member, callback)

查詢成員member在有序集合中的排序名次；但排序方式與zrevrank相反，分數最低的成員名次為0，分數越高則名次遞增。

2. 範例

TypeScript

client.del('zset:1');

const key1 = 'zset:1'
const members1 = ['c', 'a', 'C', 'A', 'B', 'b'];
const scores1 = [-2, -1, 0, 0, 1, 2];

members1.forEach((mem, ind) => {
    client.zadd(key1, scores1[ind], mem);
})
client.zrange(key1, 0, -1, (err, obj) =>{
    console.log(key1, ':', obj);
});


client.zrank(key1, 'c', (err, obj) =>{
    console.log('Rank of c :', obj);
});
client.zrank(key1, 'A', (err, obj) =>{
    console.log('Rank of A :', obj);
});
client.zrank(key1, 'b', (err, obj) =>{
    console.log('Rank of b :', obj);
});

Output-TS

zset:1 : [ 'c', 'a', 'A', 'C', 'B', 'b' ]
Rank of c : 0
Rank of A : 2
Rank of b : 5