friends.cs

自己做的的一个小的邮件系统,上传上去大家一起分享一下

using System;
using System.Data;
using System.Configuration;
using System.Web;
using System.Web.Security;
using System.Web.UI;
using System.Web.UI.WebControls;
using System.Web.UI.WebControls.WebParts;
using System.Web.UI.HtmlControls;

using System.Data.SqlClient;

public interface IFriends
{ 
    //向数据库中插入好友
    bool InsertFriends(string FriendName,string UserName);

    //删除好友
    bool DeleteFriends(int id);


    //取得所有的好友信息
    SqlDataReader GetFriendAll(string UserName);

    //判断好友是否存在
    bool IsExists(string FriendName, string UserName);

    //更新好友
    bool UpdateFriends(int id,DateTime addtime);

    string GetFriendName(int id);
    
    //通过好友名字得到好友信息
    SqlDataReader GetFriendMessageByFriendName(string FriendName);
}

/// <summary>
/// Friends 的摘要说明
/// </summary>
public class Friends :IFriends
{
    public bool InsertFriends(string FriendName,string UserName)
    {
        string connStr = ConfigurationManager.ConnectionStrings["DBConnectionStrings"].ConnectionString;
        SqlConnection conn = new SqlConnection(connStr);
        bool flag = false;
        try
        {
            if (conn.State.ToString() == "Closed")
                conn.Open();
            SqlCommand comm = new SqlCommand("insert into Friends(FriendName,UserName) values(@FriendName,@UserName)", conn);
            comm.Parameters.Add("@FriendName", SqlDbType.VarChar, 50);
            comm.Parameters.Add("@UserName", SqlDbType.VarChar, 50);
            comm.Parameters["@FriendName"].Value = FriendName;
            comm.Parameters["@UserName"].Value = UserName;

            int isOk = comm.ExecuteNonQuery();
            if (isOk > 0)
            {
                flag = true;
            }
            else
            {
                flag = false;
            }


        }
        catch (Exception ex)
        {
            throw new Exception(ex.Message, ex);
        }
        return flag;
    }

    public bool DeleteFriends(int id)
    {
        string connStr = ConfigurationManager.ConnectionStrings["DBConnectionStrings"].ConnectionString;
        string SqlStr = "DELETE from Friends where id="+id;

        SqlConnection conn = new SqlConnection(connStr);
        try
        {
            if (conn.State.ToString() == "Closed")
                conn.Open();
            int flag = 0;
            SqlCommand comm = new SqlCommand(SqlStr, conn);
            flag = comm.ExecuteNonQuery();
            if (flag > 0)
            {
                return true;
            }
            else
            {
                return false;
            }
        }
        catch (Exception ex)
        {
            throw new Exception(ex.Message, ex);
        }
    }

    public SqlDataReader GetFriendAll(string UserName)
    {
        string connStr = ConfigurationManager.ConnectionStrings["DBConnectionStrings"].ConnectionString;
        SqlConnection conn = new SqlConnection(connStr);
        string SqlStr = "select distinct id,FriendName,UserName,AddDate from Friends where UserName='"+UserName+"' order by id desc ";
        SqlDataReader dr = null;
        try
        {
            if (conn.State.ToString() == "Closed")
                conn.Open();
            SqlCommand comm = new SqlCommand(SqlStr, conn);
            dr = comm.ExecuteReader();


        }
        catch (Exception ex)
        {
            throw new Exception(ex.Message,ex);
        }
        return dr;
    }


    public bool IsExists(string FriendName, string UserName)
    {
        string connStr = ConfigurationManager.ConnectionStrings["DBConnectionStrings"].ConnectionString;
        SqlConnection conn = new SqlConnection(connStr);
        string SqlStr = "select * from Friends where FriendName='"+FriendName+"' and UserName='"+UserName+"'";
        bool flag = false;
        try
        {
            if (conn.State.ToString() == "Closed")
                conn.Open();
            SqlCommand comm = new SqlCommand(SqlStr, conn);

            SqlDataReader dr = comm.ExecuteReader();
            if (dr.Read())
            {
                flag = true;
            }
            else
            {
                flag = false;
            }
        }
        catch (Exception ex)
        {
            throw new Exception(ex.Message, ex);
        }
        return flag;
    }


    public bool UpdateFriends(int id,DateTime addtime)
    {
       
        string connStr = ConfigurationManager.ConnectionStrings["DBConnectionStrings"].ConnectionString;
        string SqlStr = "update Friends set AddDate='" + addtime + "' where id=" + id;
        bool flag = false;
        SqlConnection conn=new SqlConnection(connStr);
        try
        {
            if (conn.State.ToString() == "Closed")
                conn.Open();
            SqlCommand comm = new SqlCommand(SqlStr, conn);
            int i = comm.ExecuteNonQuery();
            comm.Dispose();

            if (i > 0)
            {
                flag = true;
            }
            else
            {
                flag = false;
            }
        }
        catch (Exception ex)
        {
            throw new Exception(ex.Message, ex);
        }
        return flag;
    }

   


    public SqlDataReader GetFriendMessageByFriendName(string FriendName)
    {
        string connStr = ConfigurationManager.ConnectionStrings["DBConnectionStrings"].ConnectionString;
        string SqlStr = "select * from Users where UserName='"+FriendName+"'";
        SqlConnection conn = new SqlConnection(connStr);
        SqlDataReader dr = null;
        try
        {
            if (conn.State.ToString() == "Closed")
                conn.Open();
            SqlCommand comm = new SqlCommand(SqlStr, conn);
            dr = comm.ExecuteReader();
            comm.Dispose();
        }
        catch (Exception ex)
        {
            if (conn.State.ToString() == "Open")
                conn.Close();
            throw new Exception(ex.Message, ex);
        }
        return dr;

    }

    public string GetFriendName(int id)
    {
        string connStr = ConfigurationManager.ConnectionStrings["DBConnectionStrings"].ConnectionString;
        SqlConnection conn = new SqlConnection(connStr);
        string name = "";
        string sqlFriendName = "select * from Friends where id="+id;

        try
        {
            if (conn.State.ToString() == "Closed")
                conn.Open();
            SqlCommand com = new SqlCommand(sqlFriendName, conn);
            SqlDataReader druser = com.ExecuteReader();
            if (druser.Read())
            {
                name = druser["FriendName"].ToString();
            }
        }
        catch (Exception ex)
        {
            throw new Exception(ex.Message, ex);
        }
        return name;
    }

}