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copied!<p>Flags enums can be treated as a simple integral type in which each individual bit corresponds to one of the flagged values. You can exploit this property to convert the bit-flagged enum value into an array of booleans, and then dispatch the methods you care about from a correlated array of delegates. </p> <p><strong>EDIT:</strong> <em>We could certainly make this code more compact through the use of LINQ and some helper functions, but I think it's easier to understand in the less sophisticated form. This may be case where maintainability trumps elegance.</em></p> <p>Here's an example:</p> <pre><code>[Flags()]public enum CheckType { Form = 1, QueryString = 2, TempData = 4, } void PerformActions( CheckType c ) { // array of bits set in the parameter {c} bool[] actionMask = { false, false, false }; // array of delegates to the corresponding actions we can invoke... Action availableActions = { DoSomething, DoSomethingElse, DoAnotherThing }; // disassemble the flags into a array of booleans for( int i = 0; i < actionMask.Length; i++ ) actionMask[i] = (c & (1 << i)) != 0; // for each set flag, dispatch the corresponding action method for( int actionIndex = 0; actionIndex < actionMask.Length; actionIndex++ ) { if( actionMask[actionIndex]) availableActions[actionIndex](); // invoke the corresponding action } } </code></pre> <p>Alternatively, if the order in which you evaluate doesn't matter, here is simpler, clearer solution that works just as well. If order does matter, replace the bit-shifting operations with an array containing the flags in the order you want to evaluate them in:</p> <pre><code>int flagMask = 1 << 31; // start with high-order bit... while( flagMask != 0 ) // loop terminates once all flags have been compared { // switch on only a single bit... switch( theCheckType & flagMask ) { case CheckType.Form: DoSomething(/*Some type of collection is passed */); break; case CheckType.QueryString: DoSomethingElse(/*Some other type of collection is passed */); break; case CheckType.TempData DoWhatever(/*Some different type of collection is passed */); break; } flagMask >>= 1; // bit-shift the flag value one bit to the right } </code></pre>

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