新手问题 有关于数据库的! 各位老师 最近看了很多的列子 他们引用连接语句的类都不相同 有用System.Data.Common的 还有用System.Data.Odbc的 还有用System.Data.SqlClient等等请问各位老师 那种引用会更好点 我用的库是sql2005 如果写连接要引用那个? 解决方案 » 免费领取超大流量手机卡,每月29元包185G流量+100分钟通话, 中国电信官方发货 sql2005的当然是System.Data.SqlClient 一般连接数据库进行操作的类都封装在数据库层。即DAL 层。你的数据库是SQL 2005的话,就引用System.Data.SqlClitent命名空间的咯 /// <summary> /// 获取所有用户信息 /// </summary> /// <returns></returns> public DataTable GetAllUser() { //初始化Connection对象 SqlConnection connection = new SqlConnection(System.Configuration.ConfigurationManager.ConnectionStrings["MSSQL"].ConnectionString); //初始化Command对象 SqlCommand command = new SqlCommand("SELECT * FROM [UserInfo]", connection); //初始化Adapter对象 SqlDataAdapter adapter = new SqlDataAdapter(); //设置Adapter对象的SelectCommand属性 adapter.SelectCommand = command; //初始化DataTable对象用以保存数据 DataTable data = new DataTable(); //填充DataTable adapter.Fill(data); return data; }ADO.NET用于访问SQL数据库的一套类库:SqlConnection,SqlCommand,SqlDataAdapter还有SqlDataReader。 上面的实例就是把对数据库的访问封装成方法的示例,如果我们需要从数据库查询,利用这个方法,传给它一个SQl语句就可以了。不用每次都写连接数据库的代码。 谢谢大家了 最近看的例子都是引用的System.Data.Common 然后在Db里引用System.Data.SqlClient 感觉上满怪异的 不知道这么写有什么好处吗?就比如: public bool HasName(string strSql) { string strConn = "Data Source=ADIR;Initial Catalog=shop;User ID=sa;Password=93626wenbo"; DbProviderFactory dbProviderFactory = DbProviderFactories.GetFactory("System.Data.SqlClient"); DbConnection dbConn = dbProviderFactory.CreateConnection(); dbConn.ConnectionString = strConn; dbConn.Open(); DbCommand dbComm = dbProviderFactory.CreateCommand(); dbComm.Connection = dbConn; dbComm.CommandText = strSql; DbDataReader reader = dbComm.ExecuteReader(); return reader.Read(); } public void ExcuteSql(string strSql) { string strConn = "Data Source=ADIR;Initial Catalog=shop;User ID=sa;Password=93626wenbo"; DbProviderFactory dbProviderFactory = DbProviderFactories.GetFactory("System.Data.SqlClient"); DbConnection dbConn = dbProviderFactory.CreateConnection(); dbConn.ConnectionString = strConn; dbConn.Open(); DbCommand dbComm = dbProviderFactory.CreateCommand(); dbComm.Connection = dbConn; dbComm.CommandText = strSql; dbComm.ExecuteNonQuery(); dbConn.Close(); dbConn.Dispose(); } public DataTable ExcuteSelect(string strSql) { string strConn = "Data Source=ADIR;Initial Catalog=shop;User ID=sa;Password=93626wenbo"; DbProviderFactory dbProviderFactory = DbProviderFactories.GetFactory("System.Data.SqlClient"); DbConnection dbConn = dbProviderFactory.CreateConnection(); dbConn.ConnectionString = strConn; dbConn.Open(); DbCommand dbComm = dbProviderFactory.CreateCommand(); dbComm.Connection = dbConn; dbComm.CommandText = strSql; DbDataAdapter adapter = dbProviderFactory.CreateDataAdapter(); adapter.SelectCommand = dbComm; DataSet dsDataSet = new DataSet(); adapter.Fill(dsDataSet,"table"); return dsDataSet.Tables["table"]; }如果要是用SqlClient写要怎么去写 还有这么写有什么坏处吗? winform中的用户控件怎么才能在asp.net 项目中使用? 关于DataGridView.Rows.Count的问题 如何从for语句跳出,并提示不同的错误? 一个简单的asp.net 问题。 求CGI开发资料!! 在图片框里点一下左键,执行一个drawstring咋不行咧。 复制DataGridView多行记录时出现乱码 请教思归、孟子word里面怎么响应drag&drop, Insert, change之类的动作! 一个奇怪的ADO.net问题! C# 符号问题 多个数据库同步数据问题 Object类对象可以转换为子类吗?
/// 获取所有用户信息
/// </summary>
/// <returns></returns>
public DataTable GetAllUser()
{
//初始化Connection对象
SqlConnection connection = new SqlConnection(System.Configuration.ConfigurationManager.ConnectionStrings["MSSQL"].ConnectionString);
//初始化Command对象
SqlCommand command = new SqlCommand("SELECT * FROM [UserInfo]", connection);
//初始化Adapter对象
SqlDataAdapter adapter = new SqlDataAdapter();
//设置Adapter对象的SelectCommand属性
adapter.SelectCommand = command;
//初始化DataTable对象用以保存数据
DataTable data = new DataTable();
//填充DataTable
adapter.Fill(data);
return data;
}ADO.NET用于访问SQL数据库的一套类库:SqlConnection,SqlCommand,SqlDataAdapter还有SqlDataReader。
就比如:
public bool HasName(string strSql)
{
string strConn = "Data Source=ADIR;Initial Catalog=shop;User ID=sa;Password=93626wenbo";
DbProviderFactory dbProviderFactory = DbProviderFactories.GetFactory("System.Data.SqlClient");
DbConnection dbConn = dbProviderFactory.CreateConnection();
dbConn.ConnectionString = strConn;
dbConn.Open();
DbCommand dbComm = dbProviderFactory.CreateCommand();
dbComm.Connection = dbConn;
dbComm.CommandText = strSql;
DbDataReader reader = dbComm.ExecuteReader();
return reader.Read();
}
public void ExcuteSql(string strSql)
{
string strConn = "Data Source=ADIR;Initial Catalog=shop;User ID=sa;Password=93626wenbo";
DbProviderFactory dbProviderFactory = DbProviderFactories.GetFactory("System.Data.SqlClient");
DbConnection dbConn = dbProviderFactory.CreateConnection();
dbConn.ConnectionString = strConn;
dbConn.Open();
DbCommand dbComm = dbProviderFactory.CreateCommand();
dbComm.Connection = dbConn;
dbComm.CommandText = strSql;
dbComm.ExecuteNonQuery();
dbConn.Close();
dbConn.Dispose();
}
public DataTable ExcuteSelect(string strSql)
{
string strConn = "Data Source=ADIR;Initial Catalog=shop;User ID=sa;Password=93626wenbo";
DbProviderFactory dbProviderFactory = DbProviderFactories.GetFactory("System.Data.SqlClient");
DbConnection dbConn = dbProviderFactory.CreateConnection();
dbConn.ConnectionString = strConn;
dbConn.Open();
DbCommand dbComm = dbProviderFactory.CreateCommand();
dbComm.Connection = dbConn;
dbComm.CommandText = strSql;
DbDataAdapter adapter = dbProviderFactory.CreateDataAdapter();
adapter.SelectCommand = dbComm;
DataSet dsDataSet = new DataSet();
adapter.Fill(dsDataSet,"table");
return dsDataSet.Tables["table"];
}
如果要是用SqlClient写要怎么去写 还有这么写有什么坏处吗?