WebMay 12, 2024 · Description: A NullReferenceException is thrown on MySqlConnection Dispose The NullReference came from the setter of the property Reader. In the getter the driver has a null check but in the setter it is treated as a NotNull value internal MySqlDataReader Reader { get { return this.driver?.reader; } set { this.driver.reader = value; … WebAug 27, 2010 · 2. I used to close an open datareader using the try/catch/finally block: Dim dr As MySqlDataReader = Nothing Try dr = DBConnection.callReadingStoredProcedure ("my_sp") Catch ex As Exception ' the caller will handle this Throw ex Finally If dr IsNot Nothing Then dr.Close () End Try. But I think it should be cleaner (and somewhat faster) to …
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WebC# Datareader未显示第一行,c#,asp.net,sqldatareader,datareader,C#,Asp.net,Sqldatareader,Datareader,我在我的数据库中循环显示一个球员所属的联赛列表。 WebOct 31, 2008 · Hi Jan. Unfortunately the SqlDataReader object doesn't have properties that Count Rows, See the work around in the code below. int RowCount = 0; using (SqlConnection myConnection = new SqlConnection("Connection String Here")) {. using (SqlCommand mySqlCommand = new SqlCommand(SQLString, myConnection)) {. my thermostat screen is blank
.NET MySql does "Using" closes the datareader? - Stack Overflow
WebTo create a MySqlDataReader, you must call the ExecuteReader method of the MySqlCommand object, rather than directly using a constructor.. System.Data.Common.DbDataReader.IsClosed and RecordsAffected are the only properties that you can call after the MySqlDataReader is closed. In some cases, you must call … WebYou can reset the CommandText property and reuse the MySqlCommand object. However, you must close the MySqlDataReader object before you can execute a new or previous command.. If an exception of type MySqlException is generated by the method executing MySqlCommand, the MySqlConnection instance remains open. It is the responsibility of … http://www.dedeyun.com/it/csharp/98822.html my thermostat\\u0027s