//下面为调用的方法 (总是跑到throw new Exception(e.Message)处,提示连接字串未初始化) string sqlString = "此处省略";
DataSet ds = new DataSet();
ds = dbConn.dsOpen(sqlString); //dbConn为自定义Class
GridView1.DataSource = ds.Tables[0];
GridView1.DataBind();
//以下为dbConn的主要内容。
//为简单起见,连接字串直接定义在这里。
public static string cnString = "此处省略";
private static SqlConnection objCn = new SqlConnection(cnString);
private static SqlCommand objCmd = new SqlCommand("", objCn);
/// <summary>
/// 打开数据库连接
/// </summary>
private static void cnOpen()
{
try
{
if (objCn.State == ConnectionState.Closed)
{
objCn.Open();
}
}
catch (Exception e)
{
throw new Exception(e.Message);
}
}
/// <summary>
/// 关闭数据库连接
/// </summary>
private static void cnClose()
{
if (objCn.State == ConnectionState.Open)
{
objCn.Close();
}
objCn.Dispose();
objCmd.Dispose();
}
/// <summary>
/// 打开一个DataSet
/// </summary>
/// <param name="sqlString"></param>
/// <returns></returns>
public static DataSet dsOpen(string sqlString)
{
DataSet ds = new DataSet();
try
{
cnOpen();
objCmd.CommandText = sqlString;
SqlDataAdapter sda = new SqlDataAdapter(objCmd);
sda.Fill(ds);
}
catch (Exception e)
{
throw new Exception(e.Message);
}
finally
{
cnClose();
}
return ds; }
using System.Data;
using System.Data.SqlClient;/// <summary>
/// DataBase 的摘要说明
/// </summary>
public class DataBase
{
public DataBase()
{
//
// TODO: 在此处添加构造函数逻辑
//
} public static DataTable SelectData(string sql)
{
using (SqlConnection sqlcon = new SqlConnection("此处省略"))
{
using (SqlDataAdapter sqladp = new SqlDataAdapter(sql, sqlcon))
{
using (DataSet ds = new DataSet())
{
sqladp.Fill(ds);
return ds.Tables[0];
}
}
}
}
}