using System;
using System.Data;
using System.Configuration;
using System.Data.SqlClient;
using System.Collections;
using System.Collections.Specialized;
using System.Data.Common;
using System.Collections.Generic;
using System.IO;
namespace Lib
{
public class SqlHelper
{
//数据库连接字符串(web.config来配置)，可以动态更改connectionString支持多数据库.
// public string path = Application.Info.DirectoryPath;
public string connectionString = "Data Source=.\\SQLEXPRESS;AttachDbFilename=|DataDirectory|\\e5mhelpsystem.mdf;Integrated Security=True;User Instance=True";
#region 公用方法
public int GetMaxID(string FieldName,string TableName)
{
string strsql = "select max(" + FieldName + ") from " + TableName;
object obj = GetSingle(strsql);
if (obj == null)
{
return 1;
}
else
{
return int.Parse(obj.ToString());
}
}
public bool Exists(string strSql, params SqlParameter[] cmdParms)
{
object obj = GetSingle(strSql, cmdParms);
int cmdresult;
if ((Object.Equals(obj, null)) || (Object.Equals(obj, System.DBNull.Value)))
{
cmdresult = 0;
}
else
{
cmdresult = int.Parse(obj.ToString());
}
if (cmdresult == 0)
{
return false;
}
else
{
return true;
}
}
#endregion
#region 执行简单SQL语句
/// <summary>
/// 执行SQL语句，返回影响的记录数
/// </summary>
/// <param name="SQLString">SQL语句</param>
/// <returns>影响的记录数</returns>
public int ExecuteSql(string SQLString)
{
using (SqlConnection connection = new SqlConnection(connectionString))
{
using (SqlCommand cmd = new SqlCommand(SQLString,connection))
{
try
{
connection.Open();
int rows=cmd.ExecuteNonQuery();
return rows;
}
catch(System.Data.SqlClient.SqlException E)
{
throw new Exception(E.Message+"<br>"+SQLString);
}
}
}
}
/// <summary>
/// 执行多条SQL语句，实现数据库事务。
/// </summary>
/// <param name="SQLStringList">多条SQL语句</param>
public void ExecuteSqlTran(ArrayList SQLStringList)
{
using (SqlConnection conn = new SqlConnection(connectionString))
{
conn.Open();
SqlCommand cmd = new SqlCommand();
cmd.Connection=conn;
SqlTransaction tx=conn.BeginTransaction();
cmd.Transaction=tx;
try
{
for(int n=0;n<SQLStringList.Count;n++)
{
string strsql=SQLStringList[n].ToString();
if (strsql.Trim().Length>1)
{
cmd.CommandText=strsql;
cmd.ExecuteNonQuery();
}
}
tx.Commit();
}
catch(System.Data.SqlClient.SqlException E)
{
tx.Rollback();
throw new Exception(E.Message);
}
}
}
/// <summary>
/// 执行带一个存储过程参数的的SQL语句。
/// </summary>
/// <param name="SQLString">SQL语句</param>
/// <param name="content">参数内容,比如一个字段是格式复杂的文章，有特殊符号，可以通过这个方式添加</param>
/// <returns>影响的记录数</returns>
public int ExecuteSql(string SQLString,string content)
{
using (SqlConnection connection = new SqlConnection(connectionString))
{
SqlCommand cmd = new SqlCommand(SQLString,connection);
System.Data.SqlClient.SqlParameter myParameter = new System.Data.SqlClient.SqlParameter ( "@content", SqlDbType.NText);
myParameter.Value = content ;
cmd.Parameters.Add(myParameter);
try
{
connection.Open();
int rows=cmd.ExecuteNonQuery();
return rows;
}
catch(System.Data.SqlClient.SqlException E)
{
throw new Exception(E.Message);
}
finally
{
cmd.Dispose();
connection.Close();
connection.Dispose();
}
}
}
/// <summary>
/// 向数据库里插入图像格式的字段(和上面情况类似的另一种实例)
/// </summary>
/// <param name="strSQL">SQL语句</param>
/// <param name="fs">图像字节,数据库的字段类型为image的情况</param>
/// <returns>影响的记录数</returns>
public int ExecuteSqlInsertImg(string strSQL,byte[] fs)
{
using (SqlConnection connection = new SqlConnection(connectionString))
{
SqlCommand cmd = new SqlCommand(strSQL,connection);
System.Data.SqlClient.SqlParameter myParameter = new System.Data.SqlClient.SqlParameter ( "@fs", SqlDbType.Image);
myParameter.Value = fs ;
cmd.Parameters.Add(myParameter);
try
{
connection.Open();
int rows=cmd.ExecuteNonQuery();
return rows;
}
catch(System.Data.SqlClient.SqlException E)
{
throw new Exception(E.Message);
}
finally
{
cmd.Dispose();
connection.Close();
connection.Dispose();
}
}
}
/// <summary>
/// 执行一条计算查询结果语句，返回查询结果（object）。
/// </summary>
/// <param name="SQLString">计算查询结果语句</param>
/// <returns>查询结果（object）</returns>
public object GetSingle(string SQLString)
{
using (SqlConnection connection = new SqlConnection(connectionString))
{
using(SqlCommand cmd = new SqlCommand(SQLString,connection))
{
try
{
connection.Open();
object obj = cmd.ExecuteScalar();
if((Object.Equals(obj,null))||(Object.Equals(obj,System.DBNull.Value)))
{
return null;
}
else
{
return obj;
}
}
catch(System.Data.SqlClient.SqlException e)
{
throw new Exception(e.Message);
}
}
}
}
/// <summary>
/// 执行查询语句，返回SqlDataReader
/// </summary>
/// <param name="strSQL">查询语句</param>
/// <returns>SqlDataReader</returns>
public SqlDataReader ExecuteReader(string strSQL)
{
SqlConnection connection = new SqlConnection(connectionString);
SqlCommand cmd = new SqlCommand(strSQL,connection);
try
{
connection.Open();
SqlDataReader myReader = cmd.ExecuteReader();
return myReader;
}
catch(System.Data.SqlClient.SqlException e)
{
throw new Exception(e.Message);
}
}
/// <summary>
/// 执行查询语句，返回结果第一行第一列的值
/// </summary>
/// <param name="strSQL"></param>
/// <returns></returns>
public string Executestring(string strSQL)
{
SqlConnection connection = new SqlConnection(connectionString);
SqlCommand cmd = new SqlCommand(strSQL, connection);
string str ="";
try
{
connection.Open();
str = (string)cmd.ExecuteScalar();
return str;
}
catch (System.Data.SqlClient.SqlException e)
{
throw new Exception(e.Message);
}
}
/// <summary>
/// 执行查询语句，返回DataSet
/// </summary>
/// <param name="SQLString">查询语句</param>
/// <returns>DataSet</returns>
public DataSet Query(string SQLString)
{
using (SqlConnection connection = new SqlConnection(connectionString))
{
DataSet ds = new DataSet();
try
{
connection.Open();
SqlDataAdapter command = new SqlDataAdapter(SQLString,connection);
command.Fill(ds,"ds");
}
catch(System.Data.SqlClient.SqlException ex)
{
throw new Exception(ex.Message);
}
return ds;
}
}
/// <summary>
/// 执行查询语句，返回DataView
/// </summary>
/// <param name="SQLString">查询语句</param>
/// <returns>DataView</returns>
public DataView QueryView(string SQLString)
{
using (SqlConnection connection = new SqlConnection(connectionString))
{
DataSet ds = new DataSet();
try
{
connection.Open();
SqlDataAdapter command = new SqlDataAdapter(SQLString, connection);
command.Fill(ds, "ds");
}
catch (System.Data.SqlClient.SqlException ex)
{
throw new Exception(SQLString + "<br>" + ex.Message);
}
connection.Close();
connection.Dispose();
return ds.Tables[0].DefaultView;
}
}
/// <summary>
/// 执行查询语句，返回DataTable
/// </summary>
/// <param name="SQLString">查询语句</param>
/// <returns>DataTable</returns>
public DataTable QueryTable(string SQLString)
{
using (SqlConnection connection = new SqlConnection(connectionString))
{
DataSet ds = new DataSet();
try
{
connection.Open();
SqlDataAdapter command = new SqlDataAdapter(SQLString, connection);
command.Fill(ds, "ds");
}
catch (System.Data.SqlClient.SqlException ex)
{
throw new Exception(ex.Message);
}
return ds.Tables[0];
}
}
#endregion
#region 执行带参数的SQL语句
/// <summary>
/// 执行SQL语句，返回影响的记录数
/// </summary>
/// <param name="SQLString">SQL语句</param>
/// <returns>影响的记录数</returns>
public int ExecuteSql(string SQLString,params SqlParameter[] cmdParms)
{
using (SqlConnection connection = new SqlConnection(connectionString))
{
using (SqlCommand cmd = new SqlCommand())
{
try
{
PrepareCommand(cmd, connection, null,SQLString, cmdParms);
int rows=cmd.ExecuteNonQuery();
cmd.Parameters.Clear();
return rows;
}
catch(System.Data.SqlClient.SqlException E)
{
throw new Exception(E.Message);
}
}
}
}
/// <summary>
/// 执行多条SQL语句，实现数据库事务。
/// </summary>
/// <param name="SQLStringList">SQL语句的哈希表（key为sql语句，value是该语句的SqlParameter[]）</param>
public void ExecuteSqlTran(Hashtable SQLStringList)
{
using (SqlConnection conn = new SqlConnection(connectionString))
{
conn.Open();
using (SqlTransaction trans = conn.BeginTransaction())
{
SqlCommand cmd = new SqlCommand();
try
{
//循环
foreach (DictionaryEntry myDE in SQLStringList)
{
string cmdText=myDE.Key.ToString();
SqlParameter[] cmdParms=(SqlParameter[])myDE.Value;
PrepareCommand(cmd,conn,trans,cmdText, cmdParms);
int val = cmd.ExecuteNonQuery();
cmd.Parameters.Clear();
trans.Commit();
}
}
catch
{
trans.Rollback();
throw;
}
}
}
}
/// <summary>
/// 执行一条计算查询结果语句，返回查询结果（object）。
/// </summary>
/// <param name="SQLString">计算查询结果语句</param>
/// <returns>查询结果（object）</returns>
public object GetSingle(string SQLString,params SqlParameter[] cmdParms)
{
using (SqlConnection connection = new SqlConnection(connectionString))
{
using (SqlCommand cmd = new SqlCommand())
{
try
{
PrepareCommand(cmd, connection, null,SQLString, cmdParms);
object obj = cmd.ExecuteScalar();
cmd.Parameters.Clear();
if((Object.Equals(obj,null))||(Object.Equals(obj,System.DBNull.Value)))
{
return null;
}
else
{
return obj;
}
}
catch(System.Data.SqlClient.SqlException e)
{
throw new Exception(e.Message);
}
}
}
}
/// <summary>
/// 执行查询语句，返回SqlDataReader
/// </summary>
/// <param name="strSQL">查询语句</param>
/// <returns>SqlDataReader</returns>
public SqlDataReader ExecuteReader(string SQLString,params SqlParameter[] cmdParms)
{
SqlConnection connection = new SqlConnection(connectionString);
SqlCommand cmd = new SqlCommand();
try
{
PrepareCommand(cmd, connection, null,SQLString, cmdParms);
SqlDataReader myReader = cmd.ExecuteReader();
cmd.Parameters.Clear();
return myReader;
}
catch(System.Data.SqlClient.SqlException e)
{
throw new Exception(e.Message);
}
}
/// <summary>
/// 执行查询语句，返回DataSet
/// </summary>
/// <param name="SQLString">查询语句</param>
/// <returns>DataSet</returns>
public DataSet Query(string SQLString,params SqlParameter[] cmdParms)
{
using (SqlConnection connection = new SqlConnection(connectionString))
{
SqlCommand cmd = new SqlCommand();
PrepareCommand(cmd, connection, null,SQLString, cmdParms);
using( SqlDataAdapter da = new SqlDataAdapter(cmd) )
{
DataSet ds = new DataSet();
try
{
da.Fill(ds,"ds");
cmd.Parameters.Clear();
}
catch(System.Data.SqlClient.SqlException ex)
{
throw new Exception(ex.Message);
}
return ds;
}
}
}
private void PrepareCommand(SqlCommand cmd,SqlConnection conn,SqlTransaction trans, 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 = CommandType.Text;//cmdType;
if (cmdParms != null)
{
foreach (SqlParameter parm in cmdParms)
cmd.Parameters.Add(parm);
}
}
#endregion
#region 存储过程操作
/// <summary>
/// 执行存储过程
/// </summary>
/// <param name="storedProcName">存储过程名</param>
/// <param name="parameters">存储过程参数</param>
/// <returns>SqlDataReader</returns>
public SqlDataReader RunProcedure(string storedProcName, IDataParameter[] parameters )
{
SqlConnection connection = new SqlConnection(connectionString);
SqlDataReader returnReader;
connection.Open();
SqlCommand command = BuildQueryCommand( connection,storedProcName, parameters );
command.CommandType = CommandType.StoredProcedure;
returnReader = command.ExecuteReader();
return returnReader;
}
/// <summary>
/// 执行存储过程
/// </summary>
/// <param name="storedProcName">存储过程名</param>
/// <param name="parameters">存储过程参数</param>
/// <param name="tableName">DataSet结果中的表名</param>
/// <returns>DataSet</returns>
public DataSet RunProcedure(string storedProcName, IDataParameter[] parameters, string tableName )
{
using (SqlConnection connection = new SqlConnection(connectionString))
{
DataSet dataSet = new DataSet();
connection.Open();
SqlDataAdapter sqlDA = new SqlDataAdapter();
sqlDA.SelectCommand = BuildQueryCommand(connection, storedProcName, parameters );
sqlDA.Fill( dataSet, tableName );
connection.Close();
return dataSet;
}
}
/// <summary>
/// 构建 SqlCommand 对象(用来返回一个结果集，而不是一个整数值)
/// </summary>
/// <param name="connection">数据库连接</param>
/// <param name="storedProcName">存储过程名</param>
/// <param name="parameters">存储过程参数</param>
/// <returns>SqlCommand</returns>
private SqlCommand BuildQueryCommand(SqlConnection connection,string storedProcName, IDataParameter[] parameters)
{
SqlCommand command = new SqlCommand( storedProcName, connection );
command.CommandType = CommandType.StoredProcedure;
foreach (SqlParameter parameter in parameters)
{
command.Parameters.Add( parameter );
}
return command;
}
/// <summary>
/// 执行存储过程，返回影响的行数
/// </summary>
/// <param name="storedProcName">存储过程名</param>
/// <param name="parameters">存储过程参数</param>
/// <param name="rowsAffected">影响的行数</param>
/// <returns></returns>
public int RunProcedure(string storedProcName, IDataParameter[] parameters, out int rowsAffected )
{
using (SqlConnection connection = new SqlConnection(connectionString))
{
int result;
connection.Open();
SqlCommand command = BuildIntCommand(connection,storedProcName, parameters );
rowsAffected = command.ExecuteNonQuery();
result = (int)command.Parameters["ReturnValue"].Value;
//Connection.Close();
return result;
}
}
/// <summary>
/// 创建 SqlCommand 对象实例(用来返回一个整数值)
/// </summary>
/// <param name="storedProcName">存储过程名</param>
/// <param name="parameters">存储过程参数</param>
/// <returns>SqlCommand 对象实例</returns>
private SqlCommand BuildIntCommand(SqlConnection connection,string storedProcName, IDataParameter[] parameters)
{
SqlCommand command = BuildQueryCommand(connection,storedProcName, parameters );
command.Parameters.Add( new SqlParameter ( "ReturnValue",
SqlDbType.Int,4,ParameterDirection.ReturnValue,
false,0,0,string.Empty,DataRowVersion.Default,null ));
return command;
}
#endregion
}
}
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顺便问一句:博客园里写文章时，工具栏上没有插入代码这个工具吗？我咋没看见呢，不会是没有吧？
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