What is the correct way to set StringBuilder.Capacity when using P / Invoke?

Question

If StringBuilder.Capacitythe maximum number of .NET characters is set, regardless of null termination, or should be set higher to reserve space for the null terminator when using P / Invoke.

The natural reaction is that it should be set one level higher, but it seems that P / Invoke should automatically compensate. In fact, it is actually registered here: http://msdn.microsoft.com/en-US/library/s9ts558h(v=VS.100).aspx

The reason for this question is that most of the examples are not fully consistent with the above documentation. Almost always, they are encoded:

StringBuilder sb = new StringBuilder(dotNetChars + 1);
SomeWindowsAPI(sb, sb.Capacity);

Instead:

StringBuilder sb = new StringBuilder(dotNetChars);
SomeWindowsAPI(sb, sb.Capacity + 1);

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Answer 1

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Answer 2

StringBuilder :

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Answer 3

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