______________________________________________________________________________ 三、OleDbdataCommand与OleDbDataReader...若要创建 OleDbDataReader，必须调用 OleDbCommand 对象的 ExecuteReader 方法，而不能直接使用构造函数。...在使用 OleDbDataReader 时，关联的 OleDbConnection 正忙于为 OleDbDataReader 服务，对 OleDbConnection 无法执行任何其他操作，只能将其关闭...除非调用 OleDbDataReader 的 Close 方法，否则会一直处于此状态。例如，在调用 Close 之前，无法检索输出参数。...command = new OleDbCommand(queryString, connection); connection.Open(); OleDbDataReader
thisCommand.ExecuteReader(); 或者 thisCommand.ExecuteNonQuery(); (这两句都可以执行sql语句) thisConnection.Close(); 将下划线部分替换为: OleDbDataReader...level”].ToString(); } 或者 if(thisReader.Read()) { string strLevel = thisReader[“level”].ToString(); } OleDbDataReader...C# 怎么从OleDbDataReader里读数据？
conn.CreateCommand(); cmd.CommandText = “select * from fruit”; conn.Open(); OleDbDataReader
ExecuteNonQuery();’由于增加了一条记录，所以返回1 // 或者MyCommand1.ExecuteReader();先增加一条记录，然后返回一个System.Data.OleDb.OleDbDataReader...ExecuteNonQuery();’由于删除了n条记录，所以返回n // 或者MyCommand1.ExecuteReader();先删除n条记录，然后返回一个System.Data.OleDb.OleDbDataReader...ExecuteNonQuery();’由于修改了1条记录，所以返回n // 或者MyCommand1.ExecuteReader();先修改了1条记录，然后返回一个System.Data.OleDb.OleDbDataReader...Equals(null)，也就是说返回结果没有任何作用 3、 executeReader方法执行SQL，（如果SQL是查询Select）返回查询结果的集合，类型是 System.Data.OleDb.OleDbDataReader...如果（如果SQL不是查询Select）那么 返回一个没有任何数据的System.Data.OleDb.OleDbDataReader类型的集合(EOF) 四、总结： ASP.Net中对于数据库的操作方法很多
cmd.ExecuteNonQuery(); cmd.CommandText = “ select a,b from B “ ; using (OleDbDataReader...cmd.ExecuteNonQuery(); cmd.CommandText = “ select a,b from B “ ; using (OleDbDataReader...cmd.ExecuteNonQuery(); cmd.CommandText = “ select a,b from B “ ; using (OleDbDataReader...cmd.ExecuteNonQuery(); cmd.CommandText = “ select a,b from B “ ; using (OleDbDataReader
myConnection.Open(); OleDbCommand myCommand = new OleDbCommand("select * from 运货商", myConnection); OleDbDataReader...myConnection.Open(); OleDbCommand myCommand = new OleDbCommand("select * from 运货商", myConnection); OleDbDataReader
但是，在执行新的命令或先前命令之前，必须关闭 OleDbDataReader。...New OleDbCommand(sql, oracleConn) cmd.Parameters.Add(“@p1”, OleDbType.Char, 3).Value = “a” Dim dr As OleDbDataReader...cmd = new OleDbCommand(sql, oracleConn); cmd.Parameters.Add(“@p1”, OleDbType.Char, 3).Value = “a”; OleDbDataReader
OleDbCommand(mySelectQuery, myConnection); myCommand.Connection.Open(); OleDbDataReader...OleDbCommand(mySelectQuery, myConnection); myCommand.Connection.Open(); OleDbDataReader...myCommand = new OleDbCommand( " Select * From [data1$A1:E25] " , myConnection ); OleDbDataReader
IsPostBack) { string id = Request.QueryString["id"]; OleDbDataReader...OleDbParameter[] para = {new OleDbParameter("uname",uname),new OleDbParameter("pwd",pwd) }; OleDbDataReader...IsPostBack) { string id = Request.QueryString["id"]; OleDbDataReader
操作数据库使用OLE DB进行数据库访问（包括增加、删除、修改和查询操作）涉及到几个关键的.NET类，主要是OleDbConnection、OleDbCommand、OleDbDataAdapter和OleDbDataReader...command = new OleDbCommand("SELECT FirstName, LastName FROM Employees", connection)) using (OleDbDataReader...OleDbDataReader: 用于读取从数据库返回的结果。注意事项确保修改连接字符串以匹配你的数据库设置。...command = new OleDbCommand("SELECT * FROM Employees", connection)) { using (OleDbDataReader...reader = (OleDbDataReader)await command.ExecuteReaderAsync()) { while
e As System.EventArgs) Handles Button1.Click Dim cmd As New OleDbCommand Dim dr As OleDbDataReader
summary> /// 用执行的数据库连接执行一个返回数据集的sql命令 /// /// /// 举例: /// OleDbDataReader...name="commandParameters">执行命令所用参数的集合 /// 包含结果的读取器 public static OleDbDataReader...conn, null, cmdText, commandParameters); //调用 SqlCommand 的 ExecuteReader 方法 OleDbDataReader
FirstDate) values('"+dic["cip"]+"','222','2018/10/15 14:35:15')", myConnection); System.Data.OleDb.OleDbDataReader
; OleDbCommand cmd = new OleDbCommand( " select * from [Subject] " , cn); OleDbDataReader...from Document Where pid = " + MasterGridView.DataKeys[e.Row.RowIndex].Value, cn1); OleDbDataReader
OleDbConnection(a); OleDbCommand cm=new OleDbCommand("select * from test2",cn); cn.Open(); OleDbDataReader
name="strSQL">查询语句 /// SqlDataReader public static OleDbDataReader...connection); try { connection.Open(); OleDbDataReader...name="strSQL">查询语句 /// SqlDataReader public static OleDbDataReader...PrepareCommand(cmd, connection, null, SQLString, cmdParms); OleDbDataReader
= null; string class1id = null; string class2id = null; OleDbDataReader...id,newstitle,newsdate from news where class2id='"+ class2id +"' and id>"+id+" order by id asc"; OleDbDataReader... id = int.Parse(inputid); string strSQL = "select * from news where id="+id; OleDbDataReader
/// sql语句的参数 /// public static OleDbDataReader
cmd = new OleDbCommand(sql, conn); DataTable dt = new DataTable(); OleDbDataReader
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