今天有位朋友leray提到想在wince上安装个嵌入式数据库，想问我一些更多的细节。
怎么说呢，其实就是按照熙熙在之前写的《WinCE平台搭建数据库（wince6.0+vs2008+sqlce）-熙熙》步骤一步一步来的，选的数据库型号很明显只能是SQLCE，这篇帖子里面已经说的很清楚了，要安装的文件在哪找、如何安装等等。用VS2005也是可以的。
另外，我再贴一段代码，用于wince数据库连接和执行SQL语句的。其实就是根据网上下载的代码改的，有的命名空间和类，加了个-ce的后缀，就 完事了。其实我自己处理有点点麻烦的就是wince系统中的路径问题，因为在这段代码中，SQL连接字符串直接连接到数据库文件的，得用程序找到这个文件 的路径才行，搞得自己一个头两个大，改天再说了，先上代码：
小二~上代码！
好嘞，客官。
using System;
using System.Collections.Generic;
using System.Text;
using System.Data.SqlServerCe;
using System.Data;
namespace TabControl
{
class sqlce_class
{
public static string Sql_conn_str = @"Data Source=db.sdf";
#region 数据库链接方法
/// <summary>
/// 取得一个连接对象
/// </summary>
/// <returns></returns>
public static SqlCeConnection GetConnection()//取得数据库链接
{
return new SqlCeConnection(Sql_conn_str);
}
public static bool TestConnection()//测试连接
{
try
{
SqlCeConnection sqlconn = GetConnection();
sqlconn.Open();
sqlconn.Close();
return true;
//MessageBox.Show("数据库可以连接！", "提示：");
}
catch
{
return false;
//MessageBox.Show("数据库连接发生错误！", "错误：");//异常提示
}
}
~sqlce_class()//析构
{
}
#endregion
#region 存在判断
/// <summary>
/// 表是否存在
/// </summary>
/// <param name="TableName"></param>
/// <returns></returns>
public static bool TabExists(string TableName)
{
string strsql = "select count(*) from sysobjects where id = object_id(N'[" + TableName + "]') and OBJECTPROPERTY(id, N'IsUserTable') = 1";
//string strsql = "SELECT count(*) FROM sys.objects WHERE object_id = OBJECT_ID(N'[dbo].[" + TableName + "]') AND type in (N'U')";
DataSet ds = sqlce_class.GetDataSetSQL(strsql);
int cmdresult;
cmdresult = int.Parse(ds.Tables[0].Rows[0][0].ToString());
return cmdresult > 0;
}
/// <summary>
/// 判断是否存在某表的某个字段
/// </summary>
/// <param name="tableName">表名称</param>
/// <param name="columnName">列名称</param>
/// <returns>是否存在</returns>
public static bool ColumnExists(string tableName, string columnName)
{
string sql = "select count(1) from syscolumns where [id]=object_id('" + tableName + "') and [name]='" + columnName + "'";
DataSet ds = sqlce_class.GetDataSetSQL(sql);
int cmdresult;
cmdresult = int.Parse(ds.Tables[0].Rows[0][0].ToString());
return cmdresult > 0;
}
public static int GetMaxID(string FieldName, string TableName)
{
string strsql = "select max(" + FieldName + ")+1 from " + TableName;
DataSet ds = sqlce_class.GetDataSetSQL(strsql);
int cmdresult;
cmdresult = int.Parse(ds.Tables[0].Rows[0][0].ToString());
return cmdresult;
}
public static bool Exists(string strSql)
{
DataSet ds = sqlce_class.GetDataSetSQL(strSql);
int cmdresult;
cmdresult = int.Parse(ds.Tables[0].Rows[0][0].ToString());
return cmdresult > 0;
}
public static bool Exists(string strSql, IDataParameter[] parameters)
{
DataSet ds = sqlce_class.GetDataSetSQL(strSql, parameters);
int cmdresult;
cmdresult = int.Parse(ds.Tables[0].Rows[0][0].ToString());
return cmdresult > 0;
}
#endregion
#region 数据库操作方法 读取、执行sql语句、
#region 读取
/// <summary>
/// 执行查询语句，返回OleDbDataReader ( 注意：调用该方法后，一定要对OleDbDataReader进行Close )
/// </summary>
/// <param name="strSQL">查询语句</param>
/// <returns>SqlCeDataReader</returns>
public static SqlCeDataReader GetReaderSQL(string strSQL)
{
SqlCeConnection connection = GetConnection();
SqlCeCommand cmd = new SqlCeCommand(strSQL, connection);
try
{
connection.Open();
SqlCeDataReader myReader = cmd.ExecuteReader(CommandBehavior.CloseConnection);
return myReader;
}
catch (System.Data.SqlServerCe.SqlCeException e)
{
throw e;
}
}
/// <summary>
/// 执行存储过程，返回OleDbDataReader ( 注意：调用该方法后，一定要对OleDbDataReader进行Close )
/// </summary>
/// <param name="storedProcName">存储过程名</param>
/// <param name="parameters">存储过程参数</param>
/// <returns>SqlCeDataReader</returns>
public static SqlCeDataReader GetReaderProc(string storedProcName, IDataParameter[] parameters)
{
SqlCeConnection connection = GetConnection();
SqlCeDataReader returnReader;
SqlCeCommand command = new SqlCeCommand(storedProcName, connection);
command.CommandType = CommandType.StoredProcedure;
foreach (SqlCeParameter parameter in parameters)
{
if (parameter != null)
{
// 检查未分配值的输出参数,将其分配以DBNull.Value.
if ((parameter.Direction == ParameterDirection.InputOutput || parameter.Direction == ParameterDirection.Input) &&
(parameter.Value == null))
{
parameter.Value = DBNull.Value;
}
command.Parameters.Add(parameter);
}
}
connection.Open();
returnReader = command.ExecuteReader(CommandBehavior.CloseConnection);
return returnReader;
}
public static DataSet GetDataSetSQL(string SQLString)
{
using (SqlCeConnection connection = GetConnection())
{
DataSet ds = new DataSet();
SqlCeDataAdapter command = new SqlCeDataAdapter(SQLString, connection);
try
{
connection.Open();
command.Fill(ds, "ds");
}
catch (System.Data.SqlServerCe.SqlCeException ex)
{
throw new Exception(ex.Message);
}
finally
{
command.Dispose();
connection.Close();
}
return ds;
}
}
public static DataSet GetDataSetSQL(SqlCeCommand cmd)
{
using (SqlCeConnection connection = GetConnection())
{
DataSet ds = new DataSet();
cmd.Connection = connection;
SqlCeDataAdapter da = new SqlCeDataAdapter(cmd);
try
{
connection.Open();
da.Fill(ds, "ds");
}
catch (System.Data.SqlServerCe.SqlCeException ex)
{
throw new Exception(ex.Message);
}
finally
{
cmd.Dispose();
da.Dispose();
connection.Close();
}
return ds;
}
}
/// <summary>
/// 执行查询语句，返回DataSet
/// </summary>
/// <param name="SQLString">查询语句</param>
/// <returns>DataSet</returns>
public static DataSet GetDataSetSQL(string SQLString, params SqlCeParameter[] cmdParms)
{
using (SqlCeConnection connection = GetConnection())
{
SqlCeCommand cmd = new SqlCeCommand();
PrepareCommand(cmd, connection, null, SQLString, cmdParms);
using (SqlCeDataAdapter da = new SqlCeDataAdapter(cmd))
{
DataSet ds = new DataSet();
try
{
da.Fill(ds, "ds");
cmd.Parameters.Clear();
}
catch (System.Data.SqlServerCe.SqlCeException ex)
{
throw new Exception(ex.Message);
}
finally
{
cmd.Dispose();
connection.Close();
}
return ds;
}
}
}
public static DataSet GetDataSetSQL(string SQLString, params IDataParameter[] cmdParms)
{
using (SqlCeConnection connection = GetConnection())
{
SqlCeCommand cmd = new SqlCeCommand();
PrepareCommand(cmd, connection, null, SQLString, cmdParms);
using (SqlCeDataAdapter da = new SqlCeDataAdapter(cmd))
{
DataSet ds = new DataSet();
try
{
da.Fill(ds, "ds");
cmd.Parameters.Clear();
}
catch (System.Data.SqlServerCe.SqlCeException ex)
{
throw new Exception(ex.Message);
}
finally
{
cmd.Dispose();
connection.Close();
}
return ds;
}
}
}
private static void PrepareCommand(SqlCeCommand cmd, SqlCeConnection conn, SqlCeTransaction trans, string cmdText, SqlCeParameter[] 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 (SqlCeParameter parameter in cmdParms)
{
if ((parameter.Direction == ParameterDirection.InputOutput || parameter.Direction == ParameterDirection.Input) &&
(parameter.Value == null))
{
parameter.Value = DBNull.Value;
}
cmd.Parameters.Add(parameter);
}
}
}
private static void PrepareCommand(SqlCeCommand cmd, SqlCeConnection conn, SqlCeTransaction trans, string cmdText, IDataParameter[] 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 (IDataParameter parameter in cmdParms)
{
if ((parameter.Direction == ParameterDirection.InputOutput || parameter.Direction == ParameterDirection.Input) &&
(parameter.Value == null))
{
parameter.Value = DBNull.Value;
}
cmd.Parameters.Add(parameter);
}
}
}
//public static OleDbDataReader Read_sql(string sql_str)//执行SQL语句——读取——返回Reader对象——它可以用作数据源的
//{
// OleDbConnection conn = Get_conn();
// OleDbDataReader read = null;
// OleDbCommand com = new OleDbCommand(sql_str,conn );//创建一个OleDbCommand对象，用于执行SQL语句
// com.CommandText = sql_str;
// //try
// //{
// conn.Open();
// read = com.ExecuteReader();//执行SQL语句，生成Reader对象
// conn.Close();
// //}
// //catch
// //{
// // conn.Dispose();
// //}
// //#if TEST
// //while (read.Read())
// //{
// // foreach (int i in read)
// // Console.WriteLine(read[i]);
// //}
// //#endif
// return read;//返回读取到的结果集
//}
//public DataView View_sql(string sql) //执行SQL语句——读取——返回DataView对象
//{
// DataSet ds = new DataSet();
// ds = Get_DataSet(sql);
// DataView dv = new DataView(ds.Tables[0]);
// return dv;
//}
#endregion
#region 执行 返回受影响的行数
/// <summary>
/// 执行单条SQL语句。
/// </summary>
/// <param name="SQLString">SQL语句</param>
/// <returns>影响的记录数</returns>
public static int ExecuteSql(string SQLString)
{
using (SqlCeConnection connection = GetConnection())
{
SqlCeCommand cmd = new SqlCeCommand(SQLString, connection);
try
{
connection.Open();
int rows = cmd.ExecuteNonQuery();
return rows;
}
catch (System.Data.SqlServerCe.SqlCeException e)
{
throw e;
}
finally
{
cmd.Dispose();
connection.Close();
}
}
}
public static int ExecuteCmd(SqlCeCommand cmd)
{
using (SqlCeConnection connection = GetConnection())
{
cmd.Connection = connection;
try
{
connection.Open();
int rows = cmd.ExecuteNonQuery();
return rows;
}
catch (System.Data.SqlServerCe.SqlCeException e)
{
throw e;
}
finally
{
cmd.Dispose();
connection.Close();
}
}
}
/// <summary>
/// 执行单条带参数的SQL语句。
/// </summary>
/// <param name="SQLString">SQL语句</param>
/// <param name="parameters">参数列表</param>
/// <returns>影响的记录数</returns>
public static int ExecuteSql(string SQLString, IDataParameter[] parameters)
{
using (SqlCeConnection connection = GetConnection())
{
SqlCeCommand command = new SqlCeCommand(SQLString, connection);
command.CommandType = CommandType.Text;
//传入参数
foreach (SqlCeParameter parameter in parameters)
{
if (parameter != null)
{
// 检查未分配值的输出参数,将其分配以DBNull.Value.
if ((parameter.Direction == ParameterDirection.InputOutput || parameter.Direction == ParameterDirection.Input) &&
(parameter.Value == null))
{
parameter.Value = DBNull.Value;
}
command.Parameters.Add(parameter);
}
}
try
{
connection.Open();
int rows = command.ExecuteNonQuery();
return rows;
}
catch (System.Data.SqlServerCe.SqlCeException e)
{
throw e;
}
finally
{
command.Dispose();
connection.Close();
}
}
}
/// <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>
/// <returns>int影响的记录数</returns>
public static int ExecuteSqlTran(List<String> SQLStringList)
{
using (SqlCeConnection conn = GetConnection())
{
conn.Open();
SqlCeCommand cmd = new SqlCeCommand();
cmd.Connection = conn;
SqlCeTransaction tx = conn.BeginTransaction();
cmd.Transaction = tx;
try
{
int count = 0;
for (int n = 0; n < SQLStringList.Count; n++)
{
string strsql = SQLStringList[n];
if (strsql.Trim().Length > 1)
{
cmd.CommandText = strsql;
count += cmd.ExecuteNonQuery();
}
}
tx.Commit();
return count;
}
catch
{
tx.Rollback();
return 0;
}
}
}
/// <summary>
/// 执行存储过程，返回受影响行数
/// </summary>
/// <param name="storedProcName">存储过程名</param>
/// <param name="parameters">存储过程参数</param>
/// <returns>int影响的记录数</returns>
public static int ExecuteProcedure(string procedureName, IDataParameter[] parameters)//执行存储过程——添加、删除、修改(存储过程名称，)
{
int count = 0;
SqlCeConnection connection = GetConnection();
SqlCeCommand command = new SqlCeCommand(procedureName, connection);//根据要执行的SQL语句和已有的数据库链接来创建一个OleDbCommand对象
command.CommandType = CommandType.StoredProcedure;//使用存储过程
//传入参数
foreach (SqlCeParameter parameter in parameters)
{
if (parameter != null)
{
// 检查未分配值的输出参数,将其分配以DBNull.Value.
if ((parameter.Direction == ParameterDirection.InputOutput || parameter.Direction == ParameterDirection.Input) &&
(parameter.Value == null))
{
parameter.Value = DBNull.Value;
}
command.Parameters.Add(parameter);
}
}
connection.Open();
count = command.ExecuteNonQuery();//执行(对数据有更改的)
command.Dispose();//释放
connection.Close();
return count;
}
#endregion
#endregion
}
}