Redis数据类型－List

lpush

在对应的list头部添加元素

127.0.0.1:6379> lpush mylist value1
(integer) 1
127.0.0.1:6379> lpush mylist value2
(integer) 2

打印出来看一下

127.0.0.1:6379> lrange mylist 0 -1
1) "value2"
2) "value1"

rpush

在对应list尾部添加元素

在下面的基础上做以下操作

127.0.0.1:6379> rpush mylist value3
(integer) 3
127.0.0.1:6379> lrange mylist 0 -1
1) "value2"
2) "value1"
3) "value3"

右以看到value3插入到了list的尾部

linsert

在key对应list的特定位置之前或之后添加字符串元素

127.0.0.1:6379> lrange mylist 0 -1
1) "value2"
2) "value1"
3) "value3"

在value1之前添加value0
127.0.0.1:6379> linsert mylist before 'value1' 'value0'
(integer) 4
127.0.0.1:6379> lrange mylist 0 -1
1) "value2"
2) "value0"
3) "value1"
4) "value3"

在之后value3之后添加value4

127.0.0.1:6379> linsert mylist after 'value3' 'value4'
(integer) 5
127.0.0.1:6379> lrange mylist 0 -1
1) "value2"
2) "value0"
3) "value1"
4) "value3"
5) "value4"

lset

根据下标设置值

127.0.0.1:6379> lrange mylist 0 -1
1) "value2"
2) "value0"
3) "value1"
4) "value3"
5) "value4"

将下标为－2的值设置成value5。-2也就是倒数第二个位置。所以value3被value5替换了
127.0.0.1:6379> lset mylist -2 value5
OK
127.0.0.1:6379> lrange mylist 0 -1
1) "value2"
2) "value0"
3) "value1"
4) "value5"
5) "value4"

lrem

从list中删除count个与value值相同的元素，

count>0时，从头到尾顺序进行删除

count<0时，从尾到头删除

count=0时，删除全部

127.0.0.1:6379> lrange mylist 0 -1
1) "value0"
2) "value2"
3) "value0"
4) "value1"
5) "value5"
6) "value4"
127.0.0.1:6379> lrem mylist 2 value0
(integer) 2
127.0.0.1:6379> lrange mylist 0 -1
1) "value2"
2) "value1"
3) "value5"
4) "value4"

ltrim

保留指定范围内的值

127.0.0.1:6379> lrange mylist 0 -1
1) "value0"
2) "value1"
3) "value2"
4) "value3"
127.0.0.1:6379> ltrim mylist 1 -2
OK
127.0.0.1:6379> lrange mylist 0 -1
1) "value1"
2) "value2"

保留第二个到倒数第二个之间的值

lpop

从头部删除一个元素，成功则返回删除的值

127.0.0.1:6379> lrange mylist 0 -1
1) "value1"
2) "value2"
3) "value3"
127.0.0.1:6379> lpop mylist
"value1"

rpop

从尾部删除一个元素，成功则返回删除的值

127.0.0.1:6379> lrange mylist 0 -1
1) "value1"
2) "value2"
3) "value3"
127.0.0.1:6379> rpop mylist
"value3"

rpoplpush

从第一个list中拿出最后一个元素，并添加到第二个list的头部

127.0.0.1:6379> lrange list1 0 -1
1) "list1_v1"
2) "list1_v2"
127.0.0.1:6379> lrange list2 0 -1
1) "list2_v1"
2) "list2_v2"
127.0.0.1:6379> rpoplpush list1 list2
"list1_v2"
127.0.0.1:6379> lrange list1 0 -1
1) "list1_v1"
127.0.0.1:6379> lrange list2 0 -1
1) "list1_v2"
2) "list2_v1"
3) "list2_v2"

lindex

通过下标拿list的到元素

127.0.0.1:6379> lrange mylist 0 -1
1) "value1"
2) "value2"
127.0.0.1:6379> lindex mylist 1
"value2"
127.0.0.1:6379> lindex mylist -1
"value2"

llen

拿到list元素的个数

127.0.0.1:6379> lrange mylist 0 -1
1) "value1"
2) "value2"
127.0.0.1:6379> llen mylist
(integer) 2