using system;
using system.collections.generic;
using system.text;
using system.collections;
using system.data.sqlclient;
using system.data;
using system.configuration;
public class SQLHelper
{
//取得数据库连接web.config 中配置
public static readonly string ConnectString = ConfigurationManager.ConnectionStrings["DBString"].ConnectionString;
///
/// 无事务，数据查询
///
/// 存储过程或Sql语句
/// 存储过程名或Sql语句内容
/// 参数列表
///
public static int ExecuteNonQuery(CommandType cmdType, string cmdText, params SqlParameter[] CommandParams)
{
SqlCommand cmd = new SqlCommand();
SqlConnection conn = new SqlConnection(ConnectString);
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try
{
PrepareCommand(cmd, conn, null, cmdType, cmdText, CommandParams);
int val = cmd.ExecuteNonQuery();
cmd.Parameters.Clear();
return val;
}
catch
{
throw;
}
finally
{
conn.Close();
}
}
///
/// 有事务，数据操作类
///
/// 事务
/// 操作类别 (stored procedure,sql)
/// 存储过程名或Sql语句
/// 参数
///
public static int ExecuteNonQuery(SqlTransaction trans, CommandType cmdType, string cmdText, params SqlParameter[] CommandParams)
{
SqlCommand cmd = new SqlCommand();
PrepareCommand(cmd, trans.Connection, trans, cmdType, cmdText, CommandParams);
/*if (cmdType == CommandType.StoredProcedure)
{
cmd.Parameters.Add("@RETURN_VALUE", "").Direction = ParameterDirection.ReturnValue;
cmd.ExecuteNonQuery();
val = (int)cmd.Parameters["@RETURN_VALUE"].Value;
}
else
if (cmdType==CommandType.Text)
{
val = cmd.ExecuteNonQuery();
}*/
int val = cmd.ExecuteNonQuery();
cmd.Parameters.Clear();
return val;
}
///
/// 返回数据集 DataReader
///
///
///
///
///
public static SqlDataReader ExecuteReader(CommandType cmdType, string cmdText, params SqlParameter[] CommandParams)
{
SqlCommand cmd = new SqlCommand();
SqlConnection conn = new SqlConnection(ConnectString);
try
{
PrepareCommand(cmd, conn, null, cmdType, cmdText, CommandParams);
SqlDataReader rdr = cmd.ExecuteReader(CommandBehavior.CloseConnection);
cmd.Parameters.Clear();
return rdr;
}
catch (Exception ex)
{
conn.Close();
// throw new Exception("操作失败！");
throw new Exception(ex.Message);
}
}
///
/// 有事务的取数据
///
///
///
///
///
///
public static SqlDataReader ExecuteReader(SqlTransaction trans, CommandType cmdType, string cmdText, params SqlParameter[] CommandParams)
{
SqlCommand cmd = new SqlCommand();
PrepareCommand(cmd, trans.Connection, trans, cmdType, cmdText, CommandParams);
SqlDataReader rdr = cmd.ExecuteReader(CommandBehavior.CloseConnection);
cmd.Parameters.Clear();
return rdr;
}
public static object ExecuteScalar(CommandType cmdType, string cmdText, params SqlParameter[] CommandParams)
{
SqlCommand cmd = new SqlCommand();
SqlConnection conn = new SqlConnection(ConnectString);
try
{
PrepareCommand(cmd, conn, null, cmdType, cmdText, CommandParams);
object val = cmd.ExecuteScalar();
cmd.Parameters.Clear();
return val;
}
catch
{
throw;
}
finally
{
conn.Close();
}
}
public static object ExecuteScalar(SqlTransaction trans, CommandType cmdType, string cmdText, params SqlParameter[] CommandParams)
{
SqlCommand cmd = new SqlCommand();
PrepareCommand(cmd, trans.Connection, trans, cmdType, cmdText, CommandParams);
object val = cmd.ExecuteScalar();
cmd.Parameters.Clear();
return val;
}
///
/// 根据Sql语句取得表
///
///
///
///
///
public static DataTable ExecuteTable(CommandType cmdType, string cmdText, params SqlParameter[] CommandParams)
{
DataTable temptable = new DataTable();
SqlCommand cmd = new SqlCommand();
SqlConnection conn = new SqlConnection(ConnectString);
try
{
PrepareCommand(cmd, conn, null, cmdType, cmdText, CommandParams);
SqlDataAdapter da = new SqlDataAdapter(cmd);
SqlCommandBuilder scb = new SqlCommandBuilder(da);
da.Fill(temptable);
}
finally
{
conn.Close();
}
return temptable;
}
public static DataTable ExecuteTable(SqlTransaction trans, CommandType cmdType, string cmdText, params SqlParameter[] CommandParams)
{
DataTable temptable = new DataTable();
SqlCommand cmd = new SqlCommand();
PrepareCommand(cmd, trans.Connection, trans, cmdType, cmdText, CommandParams);
SqlDataAdapter da = new SqlDataAdapter(cmd);
SqlCommandBuilder scb = new SqlCommandBuilder(da);
da.Fill(temptable);
cmd.Parameters.Clear();
return temptable;
}
///
/// 根据Sql语句或存储过程取得数据
///
///
///
///
///
public static DataSet ExecuteDataSet(CommandType cmdType, string cmdText, params SqlParameter[] CommandParams)
{
SqlConnection conn = new SqlConnection(ConnectString);
SqlCommand cmd = new SqlCommand();
DataSet TempDataSet = new DataSet();
try
{
PrepareCommand(cmd, conn, null, cmdType, cmdText, CommandParams);
SqlDataAdapter sqlAdapter = new SqlDataAdapter(cmd);
sqlAdapter.Fill(TempDataSet);
cmd.Parameters.Clear();
return TempDataSet;
}
finally
{
conn.Close();
}
}
public static DataSet ExecuteDataSet(SqlTransaction trans, CommandType cmdType, string cmdText, params SqlParameter[] CommandParams)
{
SqlCommand cmd = new SqlCommand();
DataSet TempDataSet = new DataSet();
PrepareCommand(cmd, trans.Connection, trans, cmdType, cmdText, CommandParams);
SqlDataAdapter sqlAdapter = new SqlDataAdapter(cmd);
sqlAdapter.Fill(TempDataSet);
cmd.Parameters.Clear();
return TempDataSet;
}
///
/// 生成Sql语句或准备
///
///
///
///
///
///
///
private static void PrepareCommand(SqlCommand cmd, SqlConnection conn, SqlTransaction trans, CommandType cmdType, string cmdText, SqlParameter[] cmdParms)
{
if (conn.State != ConnectionState.Open)
conn.Open();
cmd.Connection = conn;
cmd.CommandText = cmdText;
if (trans != null)
cmd.Transaction = trans;
cmd.CommandType = cmdType;
if (cmdParms != null)
{
foreach (SqlParameter parm in cmdParms)
cmd.Parameters.Add(parm);
}
}
public static object ToDBValue(object value)
{
return value == null ? DBNull.Value : value;
}
public static object FromDBValue(object dbValue)
{
return dbValue == DBNull.Value ? null : dbValue;
}
}
