一个实现添加、修改、删除记录的类

using System;
using System.Collections;
using System.Configuration;
using System.Data;
using System.Data.SqlClient;
namespace Data
...{
/**//// <summary>
/// </summary>
public class CData
...{
public CData()
...{
//
// TODO: 在此处添加构造函数逻辑
//
}

"数据库连接字段"#region "数据库连接字段"
/**//// <summary>
/// 联接数据库字段
/// </summary>
protected static string ss_conn = ConfigurationSettings.AppSettings["ConnectionString"];
#endregion

"执行数据库基本操作"#region "执行数据库基本操作"
/**//// <summary>
/// 执行sql语句（插入、更新、删除数据，新建、修改、删除表）
/// </summary>
/// <param name="strsql">要执行的查询SQL语句,为字符串类型string</param>
protected static void ExecuteSql(string strsql)
...{
SqlConnection sct = new SqlConnection(ss_conn);
SqlCommand scm = new SqlCommand(strsql,sct);
try
...{
sct.Open();
scm.ExecuteNonQuery();
}
catch(System.Data.SqlClient.SqlException ex)
...{
throw new Exception(ex.Message);
}
finally
...{
scm.Dispose();
sct.Close();
}
}
#endregion

"数据库数据返回"#region "数据库数据返回"
/**//// <summary>
///判断查询数据是否存在
/// </summary>
/// <param name="strsql">要执行的查询SQL语句,为字符串类型string</param>
public static bool IsExist(string strsql)
...{
SqlConnection sct = new SqlConnection(ss_conn);
SqlCommand scm = new SqlCommand(strsql,sct);
try
...{
sct.Open();
SqlDataReader sdr = scm.ExecuteReader();
if(sdr.Read())
...{
return true;
}
else
...{
return false;
}
}
catch(System.Data.SqlClient.SqlException ex)
...{
throw new Exception(ex.Message);
}
finally
...{
scm.Dispose();
sct.Close();
}
}

/**//// <summary>
///判断查询数据是否存在，并返回所需要的值
/// </summary>
/// <param name="strsql">要执行的查询SQL语句,为字符串类型string</param>
public string ReturnDataReader(string strsql)
...{
SqlConnection sct = new SqlConnection(ss_conn);
SqlCommand scm = new SqlCommand(strsql,sct);
try
...{
sct.Open();
SqlDataReader sdr = scm.ExecuteReader();
if(sdr.Read())
...{
return sdr.GetValue(0).ToString().Trim();
}
else
...{
return "null";
}
}
catch(System.Data.SqlClient.SqlException ex)
...{
throw new Exception(ex.Message);
}
finally
...{
scm.Dispose();
sct.Close();
}
}

/**//// <summary>
/// 获得数据视图
/// </summary>
/// <param name="strsql"></param>
/// <returns></returns>
public DataView ReturnDataView(string strsql)
...{
SqlConnection sct = new SqlConnection(ss_conn);
try
...{
sct.Open();
SqlDataAdapter sda = new SqlDataAdapter(strsql,sct);
DataSet ds = new DataSet();
sda.Fill(ds);
return ds.Tables[0].DefaultView ;
}
catch(System.Data.SqlClient.SqlException ex)
...{
throw new Exception(ex.Message);
}
finally
...{
sct.Close();
}
}

/**//// <summary>
/// 获得datarow(表中的某一行数据)
/// </summary>
/// <param name="strsql"></param>
/// <returns></returns>
public DataRow ReturnDataRow(string strsql)
...{
SqlConnection sct = new SqlConnection(ss_conn);
try
...{
sct.Open();
SqlDataAdapter sda = new SqlDataAdapter(strsql,sct);
DataSet ds = new DataSet();
sda.Fill(ds);
return ds.Tables[0].Rows[0];
}
catch(System.Data.SqlClient.SqlException ex)
...{
throw new Exception(ex.Message);
}
finally
...{
sct.Close();
}
}

/**//// <summary>
/// 获得数据视图
/// </summary>
/// <param name="strsql"></param>
/// <returns></returns>
public DataSet ReturnDataSet(string strsql)
...{
SqlConnection sct = new SqlConnection(ss_conn);
try
...{
sct.Open();
SqlDataAdapter sda = new SqlDataAdapter(strsql,sct);
DataSet ds = new DataSet();
sda.Fill(ds);
return ds;
}
catch(System.Data.SqlClient.SqlException ex)
...{
throw new Exception(ex.Message);
}
finally
...{
sct.Close();
}
}

#endregion
}
}