【转】redis C接口hiredis 简单函数使用介绍

时间:2023-03-09 19:39:38
【转】redis C接口hiredis 简单函数使用介绍

from : http://blog.csdn.net/kingqizhou/article/details/8104693

hiredis是redis数据库的C接口,目前只能在linux下使用,几个基本的函数就可以操作redis数据库了。

函数原型:redisContext *redisConnect(const char *ip, int port)

说明:该函数用来连接redis数据库,参数为数据库的ip地址和端口,一般redis数据库的端口为6379

该函数返回一个结构体redisContext。

函数原型:void *redisCommand(redisContext *c, const char *format, ...);

说明:该函数执行命令,就如sql数据库中的SQL语句一样,只是执行的是redis数据库中的操作命令,第一个参数为连接数据库时返回的redisContext,剩下的参数为变参,就如C标准函数printf函数一样的变参。返回值为void*,一般强制转换成为redisReply类型的进行进一步的处理。

函数原型void freeReplyObject(void *reply);

说明:释放redisCommand执行后返回的redisReply所占用的内存

函数原型:void redisFree(redisContext *c);

说明:释放redisConnect()所产生的连接。

下面用一个简单的例子说明:

#include <stdio.h>
#include <stdlib.h>
#include <stddef.h>
#include <stdarg.h>
#include <string.h>
#include <assert.h>
#include "hiredis.h" void doTest()
{
//redis默认监听端口为6387 可以再配置文件中修改
redisContext* c = redisConnect("127.0.0.1", );
if ( c->err)
{
printf("Connect to redisServer faile:%s\n",c->errstr);
redisFree(c);
return ;
}
printf("Connect to redisServer Success\n"); const char* command1 = "set stest1 value1";
redisReply* r = (redisReply*)redisCommand(c, command1); if( NULL == r)
{
printf("Execut command1 failure\n");
redisFree(c);
return;
}
if( !(r->type == REDIS_REPLY_STATUS && (strcmp(r->str,"OK")== || strcmp(r->str,"ok")== ) ))
{
printf("Failed to execute command[%s]\n",command1);
freeReplyObject(r);
redisFree(c);
return;
}
freeReplyObject(r);
printf("Succeed to execute command[%s]\n", command1); const char* command2 = "strlen stest1";
r = (redisReply*)redisCommand(c, command2);
if ( r->type != REDIS_REPLY_INTEGER)
{
printf("Failed to execute command[%s]\n",command2);
freeReplyObject(r);
redisFree(c);
return;
}
int length = r->integer;
freeReplyObject(r);
printf("The length of 'stest1' is %d.\n", length);
printf("Succeed to execute command[%s]\n", command2); const char* command3 = "get stest1";
r = (redisReply*)redisCommand(c, command3);
if ( r->type != REDIS_REPLY_STRING)
{
printf("Failed to execute command[%s]\n",command3);
freeReplyObject(r);
redisFree(c);
return;
}
printf("The value of 'stest1' is %s\n", r->str);
freeReplyObject(r);
printf("Succeed to execute command[%s]\n", command3); const char* command4 = "get stest2";
r = (redisReply*)redisCommand(c, command4);
if ( r->type != REDIS_REPLY_NIL)
{
printf("Failed to execute command[%s]\n",command4);
freeReplyObject(r);
redisFree(c);
return;
}
freeReplyObject(r);
printf("Succeed to execute command[%s]\n", command4); redisFree(c); } int main()
{
WSADATA wsaData;
int nRet;
if((nRet = WSAStartup(MAKEWORD(,),&wsaData)) != ){
printf("WSAStartup failed\n");
exit();
}
doTest();
return ;
}

执行结果为:【转】redis C接口hiredis 简单函数使用介绍