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Cursor-style iteration pattern

Note: this entry has moved.

The usual enumeration pattern in .NET is either of these:

foreach (string value in values) { // do something. } // or for (int i = 0; i < values.Length; i++) { string value = values[i]; // do something. }

When working with cursor-style APIs like the XmlReader or XPathNavigator, the pattern usual becomes something like this (note this is the same code for both APIs):

if (nav.MoveToFirstAttribute()) { do { // Do something with nav.Current. } while (nav.MoveToNextAttribute(); }

This is not as readable or compact as the usual approach. One solution to get back the for style of iteration, which I use all the time, is the following:

for (bool go = nav.MoveToFirstAttribute(); go; go = nav.MoveToNextAttribute()) { // Do something with nav.Current. }

With this approach, you can the usual iteration pattern again, and have more compact and readable code. It can be used with all XPathNavigator methods that use MoveToFirst/MoveToNext:

// To process namespaces for (bool go = nav.MoveToFirstNamespace(XPathNamespaceScope.Local); go; go = nav.MoveToNextNamespace(XPathNamespaceScope.Local)) { } // To process all child elements of current for (bool go = nav.MoveToFirstChild(); go; go = nav.MoveToNext()) { }

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