Creating c# library for mt4 - page 2
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First of all...
Try this:
First of all...
Try this:
Didnt help.
The function can return value (string) if I remove mysql related code. When I want to initialize an instance for mysql object, mt4 outputs error.
If I remove the red lines, mt4 receives any sent string. I checked all one by one.
conn = new MySql.Data.MySqlClient.MySqlConnection();
Above line raises the handle error.
[DllExport("readmysql", CallingConvention = CallingConvention.StdCall)]
public static string readmysql([MarshalAs(UnmanagedType.LPWStr)] string databasename, [MarshalAs(UnmanagedType.LPWStr)] string tablename, [MarshalAs(UnmanagedType.LPWStr)] string refereanceword, [MarshalAs(UnmanagedType.LPWStr)] string columnname, [MarshalAs(UnmanagedType.LPWStr)] string lookupcolumn){
databasename = "trydata";
tablename = "audusd";
refereanceword = "2013.06.03 04:00";
columnname = "f1";
lookupcolumn = "f2";
string getvalue;
MySql.Data.MySqlClient.MySqlConnection conn;
string myConnectionString = "server=localhost;uid=root;" + "pwd=000000;database=index;";
MySqlCommand mcd;
MySqlDataReader mdr;
conn = new MySql.Data.MySqlClient.MySqlConnection();
conn.ConnectionString = myConnectionString;
conn.Open();
string searchQuery = "SELECT * FROM `" + tablename + "` WHERE CONCAT('"+columnname+"`) LIKE '%" + refereanceword + "%'";
mcd = new MySqlCommand(searchQuery, conn);
mdr = mcd.ExecuteReader();
mdr.Close();
conn.Close();
getvalue = mdr.GetString(lookupcolumn);
return getvalue;
}
What happened, did you guys manage to solve the issue, I kind have the same issue