SqlHelper 帮助类

[code] public class SQlhelper
{
private static string strConn = ConfigurationManager.ConnectionStrings["此处填写数据库连接字符串"].ConnectionString;

/// <summary>
/// 查询
/// </summary>
/// <param name="sql">SQL语句</param>
/// <returns></returns>
public static DataTable Query(string sql)
{

using (DataTable table = new DataTable())
{
using (SqlDataAdapter sda = new SqlDataAdapter(sql, strConn))
{
sda.Fill(table);
}
return table;
}
}
/// <summary>
/// 增删改
/// </summary>
/// <param name="sql">SQL语句</param>
/// <returns></returns>
public static int NonQuery(string sql)
{
int num = 0;
using (SqlConnection conn = new SqlConnection(strConn))
{
using (SqlCommand cmd = new SqlCommand(sql, conn))
{
try
{
conn.Open();
num = cmd.ExecuteNonQuery();
}
finally
{
if (conn.State == ConnectionState.Open)
{
conn.Close();
}
}
}
}
return num;
}
}