下面是SqlHelper类，如果你对SqlHelper类不知道怎么使用，可以查看SqlHelper用法简单示例
using ...System; using System.Data; using System.Xml;
using System.Data.SqlClient; using System.Collections;
namespace Book.DAL
...{
/**////
/// SqlServer数据访问帮助类 ///
public sealed class SqlHelper ...{
私有构造函数和方法#region 私有构造函数和方法
private SqlHelper() ...{}
/**////
/// 将SqlParameter参数数组(参数值)分配给SqlCommand命令. /// 这个方法将给任何一个参数分配DBNull.Value; /// 该操作将阻止默认值的使用.
///
///
///
private static void AttachParameters(SqlCommand command, SqlParameter[] commandParameters) ...{
if( command == null ) throw new ArgumentNullException( \ if( commandParameters != null )
...{
foreach (SqlParameter p in commandParameters) ...{
if( p != null )
...{
// 检查未分配值的输出参数,将其分配以DBNull.Value.
if ( ( p.Direction == ParameterDirection.InputOutput || p.Direction == ParameterDirection.Input ) &&
(p.Value == null)) ...{ p.Value = DBNull.Value; }
command.Parameters.Add(p); } } } }
/**////
/// 将DataRow类型的列值分配到SqlParameter参数数组. ///
///
/// private static void AssignParameterValues(SqlParameter[] commandParameters, DataRow dataRow) ...{
if ((commandParameters == null) || (dataRow == null)) ...{ return; }
int i = 0;
// 设置参数值
foreach(SqlParameter commandParameter in commandParameters) ...{
// 创建参数名称,如果不存在,只抛出一个异常. if( commandParameter.ParameterName == null ||
commandParameter.ParameterName.Length <= 1 ) throw new Exception(
string.Format(\请提供参数...{0}一个有效的名称{1}.\i, commandParameter.ParameterName ) );
// 从dataRow的表中获取为参数数组中数组名称的列的索引. // 如果存在和参数名称相同的列,则将列值赋给当前名称的参数. if
(dataRow.Table.Columns.IndexOf(commandParameter.ParameterName.Substring(1)) != -1) commandParameter.Value dataRow[commandParameter.ParameterName.Substring(1)]; i++; } }
/**////
/// 将一个对象数组分配给SqlParameter参数数组.
///
/// ///
=
private static void AssignParameterValues(SqlParameter[] commandParameters, object[] parameterValues) ...{
if ((commandParameters == null) || (parameterValues == null)) ...{ return; }
// 确保对象数组个数与参数个数匹配,如果不匹配,抛出一个异常. if (commandParameters.Length != parameterValues.Length) ...{
throw new ArgumentException(\参数值个数与参数不匹配.\ }
// 给参数赋值
for (int i = 0, j = commandParameters.Length; i < j; i++)
...{
// If the current array value derives from IDbDataParameter, then assign its Value property
if (parameterValues[i] is IDbDataParameter) ...{
IDbDataParameter (IDbDataParameter)parameterValues[i]; if( paramInstance.Value == null ) ...{
paramInstance
=
commandParameters[i].Value = DBNull.Value; }
else ...{
commandParameters[i].Value = paramInstance.Value; } }
else if (parameterValues[i] == null) ...{
commandParameters[i].Value = DBNull.Value; } else
...{
commandParameters[i].Value = parameterValues[i]; } }
}
/**////
/// 预处理用户提供的命令,数据库连接/事务/命令类型/参数
///
/// ///
///
/// /// ///
///
private static void PrepareCommand(SqlCommand command, SqlConnection connection, SqlTransaction transaction, CommandType commandType, string commandText, SqlParameter[] commandParameters, out bool mustCloseConnection )
...{
if( command == null ) throw new ArgumentNullException( \ if( commandText == null || commandText.Length == 0 ) throw new ArgumentNullException( \
// If the provided connection is not open, we will open it if (connection.State != ConnectionState.Open) ...{
mustCloseConnection = true; connection.Open(); } else ...{
mustCloseConnection = false; }
// 给命令分配一个数据库连接. command.Connection = connection;
// 设置命令文本(存储过程名或SQL语句) command.CommandText = commandText;
// 分配事务 if (transaction != null) ...{
if( transaction.Connection == null ) throw new ArgumentException( \transaction was rollbacked or commited, please provide an open transaction.\ command.Transaction = transaction; }
// 设置命令类型.
command.CommandType = commandType;
// 分配命令参数
if (commandParameters != null) ...{
AttachParameters(command, commandParameters); }
return; }
#endregion 私有构造函数和方法结束
ExecuteNonQuery命令#region ExecuteNonQuery命令
/**////
/// 执行指定连接字符串,类型的SqlCommand. /// ///
/// int result = ExecuteNonQuery(connString, CommandType.StoredProcedure, \
///
///
/// /// ///
return ExecuteNonQuery(connectionString, (SqlParameter[])null); }
/**////
/// 执行指定连接字符串,类型的SqlCommand.如果没有提供参数,不返回结果. /// ///
/// int result = ExecuteNonQuery(connString, CommandType.StoredProcedure, \
///
///
///
connectionString,
CommandType
commandType, commandText,