C ++ MFC对话框-如何将连接应用于应用程序的所有对话框？

Question

I have this code to establish a connection with a MySQL database. Everytime I want my dialogs to connect to the database, I have to type the whole thing. Is there any other ways to apply it to all dialog pages? I tried to add EXTERN in front, but it says the code is being multiplied from another dialog.

unsigned short Port = 3306;
char *IPAddress = "127.0.0.1";
char *UserName = "root";
char *Password = "Root";
char *DBName = "inomatic";

MYSQL *ssock;
MYSQL_RES   *res;
MYSQL_ROW   row;
//char execsql[500];
ssock = (MYSQL *)malloc(sizeof(MYSQL));
mysql_init(ssock);
if(ssock == NULL)
{
    MessageBox("EROR: MySQL ssock init error. \n");
}
ssock = mysql_real_connect(ssock, IPAddress, UserName, Password, NULL, Port, NULL, 0);
if(!ssock)
{
    MessageBox("conn fail... \n");
    mysql_errno(ssock);
}

if(mysql_select_db(ssock, DBName) != 0)
{
    MessageBox("select db error. \n");
}

Answer 1

Create a "connection object" that holds the required Information. Make it global to your application or place it inside your CWinApp object. Initialiaze this object only once and use the global variable / singleton / CWinApp Object where you want and Need it.