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copied!<p>Supposing we have the following example class:</p> <pre><code>public class Test { public static int Add(int i1, int i2) { return i1 + i2; } public static int Add(params int[] ints) { int sum = 0; foreach (int i in ints) sum += i; return sum; } } </code></pre> <p>To get the <code>MethodInfo</code> objects for each overload of the static <code>Add</code> method you should do the following:</p> <pre><code> MethodInfo Add2Ints = typeof(Test).GetMethod("Add", new Type[] { typeof(int), typeof(int) }); MethodInfo AddParamsInts = typeof(Test).GetMethod("Add", new Type[] { typeof(int[]) }); </code></pre> <p>In order to invoke any of the two methods, symply pass the arguments with the exact type expected by the specific overload you are invoking:</p> <pre><code> Add2Ints.Invoke(null, new object[] { 1, 2 }); AddParamsInts.Invoke(null, new object[] { new int[] { 1, 2 } }); </code></pre> <p>Note that the following will not work:</p> <pre><code> AddParamsInts.Invoke(null, new object[] { 1, 2 }); </code></pre> <p>because the signature of <code>AddParmsInt</code> is really <code>(int[])</code> and although the compiler, as a courtesy, <em>allows</em> you to call such method as <code>(int, int)</code> under the hood what is really happening is that the call is converted for you at the call site to the equivalent <code>(int[])</code> call. Via reflection you don't have the compiler's "help" so you need to pass the <em>exact</em> argument type defined by the method's signature.</p> <p>With all that said, your <code>call</code> method should be as follows:</p> <pre><code> public object call(params object[] input) { return AddParamsInts.Invoke(null /*static*/, new object[] { input.Cast<int>().ToArray() }); } </code></pre> <p>Note that you can not directly cast a <code>object[]</code> array to a <code>int[]</code> array: <code>int[] ints = (int[])input</code>. Casting <em>reference</em> typed <em>arrays</em> to <em>value-type</em> arrays is not allowed.</p> <p>Also important to note is that the defined overloads of the <code>Add</code> method are useless, as they overlap. Consider only using the <code>params</code> overload or, in case you want to guarantee that at least two arguments are needed in order to evaluate an <em>addition</em>, overload them the following way:</p> <pre><code> public int Add(int i1, int i2) { } public int Add(int i1, int i2, params int[] args) { } </code></pre>

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