应用程序中的通用连接路径 [英] Connection Path Universal in application

问题描述

亲爱的所有人，

在与SQL Server的连接过程中，可以从已经定义的连接中与数据库连接.即

正如我已在类中定义以下提及的连接并在所有地方使用此连接类，而不是定义所有
返回服务器=.\ SQLEXPRESS; AttachDbFilename = F:\ jatin \ sale \ jatin_Data.MDF;集成安全性= True;连接超时= 30;用户实例= True"

现在我的问题是我可以在数据集或Crystal报表中使用此连接，以避免在每个位置出现所有连接定义问题.

亲切地指导我.

Dear All,

During the connection with SQL server could be connect with database from the already define connection. i.e

As I have define the under mention connection in a class & use this connection class at all place instead of defining all
Return "server=.\SQLEXPRESS;AttachDbFilename=F:\jatin\sale\jatin_Data.MDF;Integrated Security=True;Connect Timeout=30;User Instance=True"

Now my question is could I use this connection in the Dataset or in Crystal report to avoid all connection defination at every place.

KIndly guide me.

推荐答案

是的.由于OOP的可重用性原理，它很有可能实现.
.NET提供了ref关键字，您可以执行此操作..我将在C#中编写一个代码示例，该示例将说明与您的问题有关的用法..

yeah..its very possible thanks to re-usability principle of OOP.
.NET has come up with the ref keyword which allows you to do this very thing..I''ll put up a code sample in C# which will illustrate the usage of it in relation to your question..

.
.
/* This class contains the Connection String, connection and command object info  */
static class DB_Conn
{
  public static void Connection(ref SqlConnection conn, ref SqlCommand cmd)
  {
    conn = new SqlConnection();
    conn.ConnectionString = "[Input Connection String here]";

    cmd = new SqlCommand();
    cmd.Connection = conn;
    cmd.CommandType = CommandType.StoredProcedure; // or Text / Table
  }
}

现在，在另一个类中使用它，而不必再次创建所有内容..

Now using it in a different class without having to create everything again..

.
.
class UseData
{
  /* Now this next step is very important in order to ensure re-usability 
Declare a connection and command object  */


SqlConnection conn; /* you can set them to null if you want*/
SqlCommand cmd;

/* So to use it in a member method like below..*/

Public void deleteData(ref Conn, ref Cmd)
{
  /*Now just call the method in the 1st class and pass the connection objects in your argument list to it   */

DB_Conn.Connection(Conn,Cmd);
/* and it will set up all the connection and command objects just as was done in the method */

cmd.CommandText="[Input stored Procedure/Query string here]";

conn.Open();
cmd.ExecuteNonQuery();


if(Conn.State == ConnectionState.Open)
{
  Conn.Close();
}

cmd.Dispose();
/* This is optional but for performance reasons and good programming practice, I manually do my garbage collection */

}

}

而且您的程序应该运行顺利..
如果您喜欢上述内容，请接受答案并投票..:)

And your program should run smoothly..
If you love the above, accept answer and give it a vote..:)

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