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阴立坤的QQ空间
[csharp]
public class SqlCode
{
/// <summary>
/// 创建连接字符串
/// </summary>
/// <returns></returns>
public static SqlConnection DBCon()
{
return new SqlConnection(@"server=JACK-PCSQLEXPRESS;database=test;uid=sa;pwd=jack123"); //Sql身份验证
//Integrated Security = SSPI/Windwos 身份验证
}
/// <summary>
/// 执行查询语句
/// </summary>
/// <param name="SQLString">Sql查询语句(Select)</param>
/// <returns></returns>
public static DataSet Query(string SQLString)
{
using (SqlConnection conn = DBCon())
{
DataSet ds = new DataSet();
try
{
conn.Open();
SqlDataAdapter command = new SqlDataAdapter(SQLString, conn);
command.Fill(ds, "ds");
command.Dispose();
conn.Close();
}
catch (System.Data.SqlClient.SqlException ex)
{
throw new Exception(ex.Message);
}
return ds;
}//当connection对象执行到这里时,即被释放,帮助内存回收
}
/// <summary>
/// 执行插入、删除、更新操作
/// </summary>
/// <param name="Sql">包括 Insert、Delete、Update</param>
public static void InOrDelOrUp(string Sql)//插入数据/删除数据/更新数据
{
SqlConnection conn = DBCon();
conn.Open();
SqlCommand cmd = new SqlCommand(Sql, conn);
cmd.ExecuteNonQuery();
cmd.Dispose();
conn.Close();
}
/// <summary>
/// 判断是否存在
/// </summary>
/// <param name="Username">字符串</param>
/// <returns></returns>
public static bool CheckName(string Username)
{
SqlConnection conn = DBCon();
conn.Open();
SqlCommand cmd = new SqlCommand("select * from stu where sName="" + Username + """, conn);
cmd.ExecuteNonQuery();
if (null != cmd.ExecuteScalar())
{
cmd.Dispose();
conn.Close();
return false;
}
else
{
cmd.Dispose();
conn.Close();
return true;
}
}
}
[/csharp]