使用oledb操作数据库工具类，可使用泛型统一操作
using System;
using System.Collections.Generic;
using System.Data;
using System.Data.OleDb;
using System.Linq;
using System.Reflection;
using System.Text;
using System.Windows.Forms;
namespace CommonUtil
{
public class DataBaseUtil
{
//传递数据库文件路径，这里使用的是access2007数据库
public DataBaseUtil(string path)
{
Path = path;
ConnStr = string.Format(@"Provider=Microsoft.ACE.OLEDB.12.0;Data Source={0};Persist Security Info=False; ",
path);
conn = new OleDbConnection(ConnStr);
}
public string Path;
public static string ConnStr = @"Provider=Microsoft.ACE.OLEDB.12.0;Data Source=E:\\numdb.accdb;Persist Security Info=False; ";
private OleDbConnection conn= new OleDbConnection(ConnStr);//创建一个connection对象
//使用泛型，获取所有的实体类对象，返回list
public List<T> ReieveList<T>() where T : class,new()
{
try
{
var className = (typeof(T)).Name;
var sql = string.Format("SELECT * FROM {0}", className);
OleDbDataAdapter da = new OleDbDataAdapter(sql, ConnStr);
DataSet ds = new DataSet();
da.Fill(ds);
var dt = ds.Tables[0];
var list = ConverterUtil.ConvertDataTableToList<T>(dt);
return list;
}
catch (Exception e)
{
MessageBox.Show(e.Message);
return null;
}
}
//同上，根据条件，查询，返回list实体类列表
public List<T> ReieveList<T>(string where) where T : class,new()
{
try
{
var className = (typeof(T)).Name;
var sql = string.Format("SELECT * FROM {0} {1}", className,where);
OleDbDataAdapter da = new OleDbDataAdapter(sql, ConnStr);
DataSet ds = new DataSet();
da.Fill(ds);
var dt = ds.Tables[0];
var list = ConverterUtil.ConvertDataTableToList<T>(dt);
return list;
}
catch (Exception e)
{
MessageBox.Show(e.Message);
return null;
}
}
//插入一条数据
public bool Insert<T>(T entity) where T : class,new()
{
try
{
var type = typeof (T);
var className = type.Name;
var fields = "";
var values = "";
foreach (var property in type.GetProperties())
{
if (property.Name.Equals("ID")) continue;
fields += "," + property.Name;
var isNumStr = (property.PropertyType == typeof (double) ||
property.PropertyType == typeof (int))
? ""
: "‘";
values += "," + isNumStr + property.GetValue(entity, null) + isNumStr;
}
fields = fields.Substring(1);
values = values.Substring(1);
var sql = string.Format("insert into {0}({1}) values ({2}) ", className,
fields, values);
OleDbDataAdapter da = new OleDbDataAdapter();
da.InsertCommand = new OleDbCommand(sql, conn);
da.InsertCommand.CommandText = sql;
conn.Open();
da.InsertCommand.ExecuteNonQuery();
conn.Close();
return true;
}
catch (Exception e)
{
MessageBox.Show(e.Message);
return false;
}
finally
{
conn.Close();
}
}
//更新实体类
public bool Update<T>(T entity) where T : class,new()
{
try
{
var type = typeof(T);
var className = type.Name;
var values = "";
var id = "";
foreach (var property in type.GetProperties())
{
if (property.Name.Equals("ID"))
{
id = " where ID="+ property.GetValue(entity, null).ToString();
continue;
}
var isNumStr = (property.PropertyType == typeof(double) ||
property.PropertyType == typeof(int))
? ""
: "‘";
values += "," +property.Name +"="+ isNumStr + property.GetValue(entity, null) + isNumStr;
}
values = values.Substring(1);
var sql = string.Format("update {0} set {1} {2}", className,
values,id);
OleDbDataAdapter da = new OleDbDataAdapter();
da.UpdateCommand = new OleDbCommand(sql, conn);
da.UpdateCommand.CommandText = sql;
conn.Open();
da.UpdateCommand.ExecuteNonQuery();
conn.Close();
return true;
}
catch (Exception e)
{
MessageBox.Show(e.Message);
return false;
}
finally
{
conn.Close();
}
}
//根据条件删除数据
public bool Delete<T>(string where)
{
try
{
var type = typeof(T);
var className = type.Name;
var sql = string.Format("delete from {0} {1}", className,
where);
OleDbDataAdapter da = new OleDbDataAdapter();
da.DeleteCommand = new OleDbCommand(sql, conn);
da.DeleteCommand.CommandText = sql;
conn.Open();
da.DeleteCommand.ExecuteNonQuery();
conn.Close();
return true;
}
catch (Exception e)
{
MessageBox.Show(e.Message);
return false;
}
finally
{
conn.Close();
}
}
//批量插入数据
public bool InsertList<T>(List<T> entitysList) where T : class,new()
{
try
{
var type = typeof (T);
var className = type.Name;
var fields = "";
var values = "";
foreach (var property in type.GetProperties())
{
if (property.Name.Equals("ID")) continue;
fields += "," + property.Name;
var isNumStr = (property.PropertyType == typeof (double) ||
property.PropertyType == typeof (int))
? ""
: "‘";
values += ",?" ;
}
fields = fields.Substring(1);
values = values.Substring(1);
var sql = string.Format("insert into {0}({1}) values ({2}) ", className,
fields, values);
OleDbDataAdapter da = new OleDbDataAdapter();
da.InsertCommand = new OleDbCommand(sql, conn);
da.InsertCommand.CommandText = sql;
foreach (var property in type.GetProperties())
{
if (property.Name.Equals("ID")) continue;
var oleType = (property.PropertyType == typeof(double) ||
property.PropertyType == typeof(int))
? OleDbType.Integer
: OleDbType.VarChar;
da.InsertCommand.Parameters.Add(property.Name, oleType, int.MaxValue,
property.Name);
fields += "," + property.Name;
values += ",?";
}
var table = ConverterUtil.ConvertListToDataTable(entitysList);
table.TableName = className;
da.Update(table);
return true;
}
catch (Exception e)
{
MessageBox.Show(e.Message);
return false;
}
finally
{
conn.Close();
}
}
//这个方法是用来执行无返回结果的插入语句，如 insert select
public bool ExecuteInsertSql(string sql)
{
try
{
OleDbDataAdapter da = new OleDbDataAdapter();
da.InsertCommand = new OleDbCommand(sql, conn);
da.InsertCommand.CommandText = sql;
conn.Open();
da.InsertCommand.ExecuteNonQuery();
conn.Close();
return true;
}
catch (Exception e)
{
MessageBox.Show(e.Message);
return false;
}
finally
{
conn.Close();
}
}
}
}