写个公用类: public class DBConn { public SqlConnection conn = null; public DBConn { conn = new SqlConnection("server=serverName;uid=sa;pwd=123;database=yourDB"); } }在其他类中引用 DBConn connTest = new DBConn(); connTest.Open();
最后一句写错了,应该是connTest.conn.Open();
public class After_Service_Info { ............... private myConn.myConn myConn = new myConn.myConn(); .................... public bool DeleteInfoToDB() { string str_del = "delete from t1 where (编号='" + ID + "')"; System.Data.SqlClient.SqlConnection conn = new System.Data.SqlClient.SqlConnection(str_conn); System.Data.SqlClient.SqlCommand Delete=new System.Data.SqlClient.SqlCommand(str_del,conn); Delete.Connection.Open(); try { Delete.ExecuteNonQuery(); Delete.Connection.Close(); } catch { ................ } } }
using System; using System.Data; using System.Data.SqlClient; using System.Collections; using System.Configuration;namespace Cconnection {
/// <summary> /// DbControl 的摘要说明。 /// </summary> public class DBControl { public static DataSet DBSet; public static string txtSQL; public static SqlConnection sqlConn = new SqlConnection(); public DBControl() {
} public static DataSet GetDataSet(string sql) { DataSet ds = new DataSet();
public ADODB.Connection conn;
如果你的winform的,在当前form里就可以直接用这个变量了,如果其它from要用,则要通过当前form来引用。关于如何引用看看这个http://community.csdn.net/Expert/topic/3472/3472755.xml?temp=.6977045
{
/// <summary>
/// Conn 的摘要说明。
/// </summary>
public class myConn
{
private string _ErrString; /// <summary>
/// 获取错误信息
/// </summary>
public string ErrString
{
get
{
return ErrString;
}
}
/// <summary>
/// Conn类的无参数构造函数
/// </summary>
public myConn()
{
//
// TODO: 在此处添加构造函数逻辑
//
this._ErrString = "";
} /// <summary>
/// 通过SQL语句返回一个DataTable
/// </summary>
/// <param name="_strConn">连接字符串</param>
/// <param name="_strSql">查询语句</param>
/// <param name="_DataTable">需要返回的Table</param>
/// <returns>如果成功返回true,否则返回false</returns>
public bool GetTable(string _strConn,string _strSql,ref System.Data.DataTable _DataTable)
{
try
{
System.Data.SqlClient.SqlConnection myConn = new System.Data.SqlClient.SqlConnection(_strConn);
System.Data.SqlClient.SqlDataAdapter myAd = new System.Data.SqlClient.SqlDataAdapter(_strSql,myConn);
System.Data.DataSet ds = new System.Data.DataSet(); myAd.Fill(ds,"myTable");
_DataTable = ds.Tables["myTable"];
return true;
}
catch(Exception err)
{
this._ErrString = _strSql + "\n" + err.Message;
return false;
}
} public bool ExcQuery( string _strConn, string _strSql)
{
System.Data.SqlClient.SqlConnection myConn = new System.Data.SqlClient.SqlConnection();
try
{
myConn.ConnectionString = _strConn;
myConn.Open();
System.Data.SqlClient.SqlCommand myComm = new System.Data.SqlClient.SqlCommand(_strSql, myConn);
myComm.ExecuteNonQuery();
myConn.Close();
return true;
}
catch (Exception err)
{
_ErrString = _strSql + "\n" + err.Message;
// _ErrString = htmlchangechar(_ErrString);
return false;
}
}
}
}
public class DBConn
{
public SqlConnection conn = null; public DBConn
{
conn = new SqlConnection("server=serverName;uid=sa;pwd=123;database=yourDB");
}
}在其他类中引用
DBConn connTest = new DBConn();
connTest.Open();
{
...............
private myConn.myConn myConn = new myConn.myConn(); ....................
public bool DeleteInfoToDB()
{
string str_del = "delete from t1 where (编号='" + ID + "')";
System.Data.SqlClient.SqlConnection conn = new System.Data.SqlClient.SqlConnection(str_conn);
System.Data.SqlClient.SqlCommand Delete=new System.Data.SqlClient.SqlCommand(str_del,conn);
Delete.Connection.Open();
try
{
Delete.ExecuteNonQuery();
Delete.Connection.Close();
}
catch
{
................
}
}
}
using System.Data;
using System.Data.SqlClient;
using System.Collections;
using System.Configuration;namespace Cconnection
{
/// <summary>
/// DbControl 的摘要说明。
/// </summary>
public class DBControl
{
public static DataSet DBSet;
public static string txtSQL;
public static SqlConnection sqlConn = new SqlConnection();
public DBControl()
{
}
public static DataSet GetDataSet(string sql)
{
DataSet ds = new DataSet();
try
{
sqlConn = new SqlConnection(ConfigurationSettings.AppSettings["sqlConn"]);
SqlDataAdapter sqlApt = new SqlDataAdapter(sql, sqlConn);
sqlApt.Fill(ds);
return ds;
}
catch (Exception ex)
{
throw (ex);
}
} public static int ExecuteSQL(string sql)
{
try
{
sqlConn = new SqlConnection(ConfigurationSettings.AppSettings["sqlConn"]);
SqlCommand sqlCmd =new SqlCommand(sql,sqlConn);
sqlConn.Open();
return sqlCmd.ExecuteNonQuery();
}
catch (Exception ex)
{
throw (ex);
}
finally
{
sqlConn.Close();
}
}
}
}
静态函数,可以全局调用
[email protected]
呵呵