// mysql_dll.cpp : Defines the entry point for the DLL application.
#include "stdafx.h"
#include "stdlib.h"
MYSQL *conn=NULL;
MYSQL_RES *p_res_ptr=NULL;
MYSQL_ROW sqlrows;
BOOL APIENTRY DllMain( HANDLE hModule,
DWORD ul_reason_for_call,
LPVOID lpReserved
)
{
return TRUE;
}
extern "C" int _declspec(dllexport) init_mysql_connection(char *str_server,char *str_username,char *str_pwd,char *str_Table)
{
conn=mysql_init(NULL);
if(!conn)
{
printf("\nFailed to initate MySQL connection");
return 1;
exit(0);
}
else
{
printf("\nSuccess to initate MySQL connection");
if (!mysql_real_connect(conn,str_server,str_username,str_pwd,str_Table,0,NULL,0))
{
printf( "Failed to connect to MySQL: Error: %s\n", mysql_error(conn));
}
else
{
printf("\nLogged on to %s sucessfully",str_server);
return 0;
}
return 0;
}
}
extern "C" int _declspec(dllexport) close_mysql_connection()
{
if(conn=NULL)
{
printf("\nConnection is Null");
return 1;
exit(0);
}
else
{
mysql_free_result(p_res_ptr);
printf("\nClose connection");
mysql_close(conn);
return 0;
}
}
//"show status like \'qcache%\'"
extern "C" int _declspec(dllexport) get_mysql_table_query(char *str_query)
{
int res=0;
res=mysql_query(conn,str_query);
if(res)
{
printf("Failed to mysql query: Error: %s\n", mysql_error(conn));
return 1;
}
else
{
printf("\nSucess in Mysql Query");
return 0;
}
}
extern "C" int _declspec(dllexport) get_mysql_query_data(char *str_query,char *str_data)
{
unsigned long u1_numrow=0;
unsigned int i_index = 0;
p_res_ptr=mysql_use_result(conn);
if(p_res_ptr){
while((sqlrows=mysql_fetch_row(p_res_ptr))){
if(*sqlrows[0]=*str_query)
{
strcpy(str_data,sqlrows[1]);
}
}
}
return NULL;
}
lr 9.1中代码：
Action()
{
int i=0;
double x;
char *str_data;
str_data=(char *)malloc(20*sizeof(char));
lr_load_dll("D:\\vc\\mysql_dll\\Debug\\mysql_dll.dll");
i= init_mysql_connection("localhost","root","123456","mysql");
lr_output_message("%d",i);
for(;;)
{
get_mysql_query_data("Qcache_hits",str_data);
i=get_mysql_table_query("show status like \'qcache%\'");
lr_output_message("%d",i);
x = atof(str_data);
lr_user_data_point("hits",x);
lr_think_time(5);
}
lr_output_message("%d",x);
close_mysql_connection();
return 0;
}
