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copied!<p>Your code for accessing the SQLDataReader object looks correct.</p> <p>If I understand you properly, this <code>while</code> loop is not being run:</p> <pre><code> //Empiezo el ciclo while (usuarioDR.Read()) { MessageBox.Show("Paso por aca 2"); // <- It does not execute if (usuarioDR["fechahora"].ToString() != "") { MessageBox.Show("Paso por aca 3"); tipo = (DateTime)usuarioDR["fechahora"]; MessageBox.Show(tipo.ToString()); } else { validar = true; MessageBox.Show("Paso por aca 1"); } } </code></pre> <p>If this loop is not being run, it is because the <code>usuarioDR.Read()</code> function is returning a value of <code>false</code>. Here's some things to try and figure out what is going wrong:</p> <p>Start debugging your code - a good first step would be to put a breakpoint at <code>while (usuarioDR.Read())</code> and see what information is contained in the <code>usuarioDR</code> object at that point in your function. Is there anything in the <code>usuarioDR</code> object? If there isn't, that means nothing is being pushed into <code>usarioDR</code> when you call <code>ExecuteReader()</code>.</p> <p>Try approaching this from the other end - write out your <code>"SELECT TOP 1 * FROM movimiento_docente WHERE (ID = @cedula) ORDER BY id_movimiento DESC"</code> query in the Server Management Studio with a test value for <code>@cedula</code>. Does it generate the results you expect? If it does, then that means that your issue lies within your code and how it accesses the database.</p> <p>In the end, I think it's going to come down to the standard debugging process: Set up breakpoints, step through your code, and check the data in your objects to see if it meets your expectations. </p> <p>One place to start looking might be at your <code>usarioDR</code> object. You start by initializing it as <code>null</code>; is it still <code>null</code> after you run the line <code>usuarioDR = usuario.ExecuteReader();</code>? If it is, that might help you narrow your search. </p>

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