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POC# Reflection: Instantiate an object with string class name
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  1. POC# Reflection: Instantiate an object with string class name
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    copied!<p>my situation is the next: I'm working with Visual C# 2010 express developing a Windows Forms Application. When the user logins, dinamically build a menustrip with options loaded from a database table. In that table i save id, option name and Form Name.</p> <p>So, suppose that in my project i have a Form named Contabilidad, it has Contabilidad.cs that is the main class , so if i wanna create a new form and show it i do this:</p> <pre><code>Contabilidad frmConta = new Contabilidad(); frmConta.Show(); </code></pre> <p>But in this case, because the menu options are stored in database, in database i only have the string "Contabilidad". So, i want to use C# reflection to create a instance of Contabilidad or any other form only with class name in string format.</p> <p>First i tried this:</p> <pre><code>Form frmConta= (Form)Activator.CreateInstance(null, "Contabilidad").Unwrap(); </code></pre> <p>Because i read in a StackOverflow question that if i use null i'm referring to current assembly (my forms are all in the same project), but i get this message:</p> <pre><code>Could not load type 'Contabilidad' from assembly 'AccountingSA, Version=1.0.0.0, Culture=neutral, PublicKeyToken=null'. </code></pre> <p>The class definition is the next:</p> <pre><code>namespace AccountingSA { public partial class Contabilidad : Form { public Contabilidad() { InitializeComponent(); } ... </code></pre> <p>Also i tried this:</p> <pre><code>Assembly assembly = Assembly.Load("AccountingSA"); Type t = assembly.GetType("Contabilidad"); Form frmConta = (Form)Activator.CreateInstance(t); </code></pre> <p>But i get ArgumentNullException with this message:</p> <pre><code>Value cannot be null. Parameter name: type </code></pre> <p>Because t variable is null.</p> <p>What i'm do wrong? Thanks in advance.</p>
 

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