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این هم کد خطا استاد:

ExecuteReader: CommandText property has not been initialized

Description: An unhandled exception occurred during the execution of the current web request. Please review the stack trace for more information about the error and where it originated in the code. 

Exception Details: System.InvalidOperationException: ExecuteReader: CommandText property has not been initialized

Source Error: 

         
Line 154:            con4.Open();
Line 155:            da4.Fill(dt4);      خط خطا
Line 156:            con4.Close();

کد کامل را قرار دهید

da4 یک Adapter هست ؟

بله یک Adapter  هست.

اینهم کد کامل :

DataTable dt4 = new DataTable();
            string strconstring4;
            strconstring4 = ConfigurationSettings.AppSettings["constring"];
            SqlConnection con4 = new SqlConnection(strconstring4);
            SqlDataAdapter da4 = new SqlDataAdapter();
            da4.SelectCommand = new SqlCommand();
            da4.SelectCommand.Connection = con4;
            
            for (int i = 0; i < dt4.Rows.Count-1; i++)
            {
                string horof1; 
               horof1 = Persian_Number_To_String.GET_Number_To_PersianString(Convert.ToString (dt4.Rows[i]["saham"]));

                da4.SelectCommand.CommandText = ("update Memberprintsaham set sahamh=N'" + horof1 + "'");    
            }
            
            con4.Open();
            da4.Fill(dt4);
            con4.Close();