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PODynamically coerce primitive type from one to another?
 

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    <p>I'm working on a rather tricky problem. At the very high level, I have an object which is a primitive and I need to coerce it into a different primitive type in C#. The values <strong>and the types</strong> are determined at runtime.</p> <p>I tried roughly this (my code is more complex, this demonstrates the problem):</p> <pre><code>object value = (int)0x8ba9dc90; Type t = typeof(UInt64); object result = Convert.ChangeType(value, t); </code></pre> <p>This works some of the time, except in the case (as above) where an overflow or underflow would occur.</p> <p>What I <em>want</em> to happen is that coercion (instead of conversion) would occur. In this case, I'd simply like that "(int)0x8ba9dc90" to be "(ulong)0x8ba9dc90". Similar with floats: if value = "(float)-32.01" and "t" is "UInt64", I want the result to be "0xffffffffffffffe0". Which is exactly what you get when you run "unchecked { ulong u = (ulong)(double)-32.01; }"</p> <p>Is there any way to do this, or am I stuck writing a custom converter?</p> <p>(Yes, I realize this is an odd thing to try to do. This is all highly dynamic code, and I'm trying to do coercion in a DynamicObject.TryConvert override. I also am fully aware there are a lot of cases this will throw away data through down casts, etc. That's perfectly fine in my application. I just can't figure out how to write this without a giant nested switch statement.)</p> <p><strong>EDIT:</strong> To be clear my function looks something like this:</p> <pre><code>public override bool TryConvert(ConvertBinder binder, out object result) { if (binder.Type.IsPrimitive &amp;&amp; m_type.IsPrimitive) { // m_type is System.Type, which is m_value's current type. // m_value is System.Object, contains a primitive value. // binder.Type is the System.Type I need to coerce m_value into. result = Convert.ChangeType(m_value, binder.Type); return true; } result = null; return false; } </code></pre>
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    1. COHave you tried using `dynamic`?
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    2. COTried what with dynamic? The both "value" and "t" are not known at compile time. I can't write something like "(ulong)(dynamic)value", as "ulong" is part of what is a parameter to this function, it comes as a "Type" parameter.
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    3. COWhat about http://stackoverflow.com/questions/1068541/how-to-convert-a-value-type-to-byte-in-c?
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