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    <p>You can use either <code>Activator.CreateInstance&lt;T&gt;()</code> or invoke the constructor via <code>typeof(T).GetConstructor(...).Invoke(new object[] { ... });</code></p> <p>If you need alot of this operations; you can also use <code>Expression.New</code> to create them; as <code>CreateInstance</code> and via the constructor are quite expensive methods.</p> <hr> <p>Example of doing it the Expression based way.</p> <pre><code> private void Foo() { TestJan myObject = CreateObject&lt;TestJan&gt;("Jan", 21); } private T CreateObject&lt;T&gt;(string name, int age) { //first get a reference to the ConstructorInfo //we know constructor has 2 params, string and int32. Names are not important. System.Reflection.ConstructorInfo ci = typeof(T).GetConstructor(new[] { typeof(string), typeof(int) }); //we now have to define the types ParameterExpression stringParam = Expression.Parameter(typeof(string), "stringExp"); ParameterExpression intParam = Expression.Parameter(typeof(int), "intExp"); //create an expression NewExpression constructor = Expression.New(ci, stringParam, intParam); //wrap this in a lambda-expression, which returns basically // (stringExp, intExp) =&gt; new T(stringExp, intExp); LambdaExpression lambda = Expression.Lambda(constructor, stringParam, intParam); //compile into delegate var constructorDelegate = (Func&lt;string, int, T&gt;)lambda.Compile(); //invoke the delegate. Normally you would cache this in a static Dictionary&lt;Type, Delegate&gt;. //when you cache this, it's lightning fast. As it's just as fast as hard program // (stringExp, intExp) =&gt; new T(stringExp, intExp); return constructorDelegate.Invoke(name, age); } </code></pre> <p>You can vary of course with the parameters and such, I find this the way best way to create an object, because it's both fast and flexible.</p>
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    1. PODataTable into List<T> *without* where T : class, new() - potential problems?
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    1. USJan Jongboom
    1. USJan Jongboom
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    1. COSee my answer to Dzmitry re Activator.CreateInstance - I've not tried GetConstructor but share your concern about expense.
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      1. USMike Kingscott
    2. COIf you really care about the performance. You should create a compiled Expression tree, using `Expression.New`, then wrap it in an `Expression.Lambda` and then `.Compile()` to get a reusable delegate that does it as fast as native code.
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      1. USJan Jongboom
    3. CO@Jan, you big, me small - that's over my head :-s For my edification, could I see some pseudo-code / code for what you describe? It would help me and others, thank you :-)
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