.net/c#连接sqlserver

Webconfig代码

<configuration>

<appSettings>

<add key="myconnect" value="server=.;UID=sa;password='1';database=test" />

</appSettings>

</configuration>

 

数据库类代码

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;

 

/// <summary>

///DB_class 的摘要说明

/// </summary>

public class DB_class

{

SqlConnection myconn;

SqlCommand mycmd;

DataSet ds; //数据集

SqlDataAdapter adapt;

    public DB_class()

    {

        //

        //TODO: 在此处添加构造函数逻辑

        //

    }

public SqlConnection GetConnection()

{

string mystr = ConfigurationManager.AppSettings["myconnect"].ToString();

SqlConnection myconn = new SqlConnection(mystr);

return myconn;

}

 

public int ExecNonQuery(string strSql)

{

 

try

{

myconn = GetConnection();//与数据库连接

mycmd = new SqlCommand();//初始化SqlCommand类对象

mycmd.Connection = myconn;

mycmd.CommandText = strSql;

if (mycmd.Connection.State != ConnectionState.Open)

{

mycmd.Connection.Open();//打开与数据库的连接

}

int a=mycmd.ExecuteNonQuery();//执行Sql操作，并返回受影响的行数

return a;

 

}

catch (Exception ex)

{

throw new Exception(ex.Message, ex);

 

}

finally

{

if (mycmd.Connection.State == ConnectionState.Open)

{//断开连接，释放资源

mycmd.Connection.Close();

myconn.Dispose();

mycmd.Dispose();

 

}

}

}

 

public string ExecScalar(string strSql)

{

try

{

myconn = GetConnection();//与数据库连接

mycmd = new SqlCommand();//初始化SqlCommand类对象

mycmd.Connection = myconn;

mycmd.CommandText = strSql;

if (mycmd.Connection.State != ConnectionState.Open)

{

mycmd.Connection.Open();//打开与数据库的连接

}

//使用SqlCommand对象的ExecuteScalar方法返回第一行第一列的值

//strSql = Convert.ToString(mycmd.ExecuteScalar());

string another = Convert.ToString(mycmd.ExecuteScalar());

return another;

}

catch (Exception ex)

{

throw new Exception(ex.Message, ex);

 

}

finally

{

if (mycmd.Connection.State == ConnectionState.Open)

{//断开连接，释放资源

myconn.Dispose();

mycmd.Connection.Close();

mycmd.Dispose();

 

}

}

}

 

public DataTable GetDataSet(string strSql, string TableName)

{

ds = new DataSet();

try

{

myconn = GetConnection();//与数据库连接

adapt = new SqlDataAdapter(strSql, myconn); //实例化SqlDataAdapter类对象

adapt.Fill(ds, TableName);//填充数据集

return ds.Tables[TableName];//返回数据集DataSet的表的集合

 

}

catch (Exception ex)

{

throw new Exception(ex.Message, ex);

 

}

finally

{//断开连接，释放资源

myconn.Close();

adapt.Dispose();

ds.Dispose();

myconn.Dispose();

}

 

}

}