The .NET Framework provides the System.String data type to represent a string. Intensive string manipulation can degrade performance. Every time you perform an operation to change string data, the original string in memory is discarded for later garbage collection and a new one is created to hold the new string data. Also note that the String type is a reference type, so the contents of the string are stored on the managed heap. As a result, strings must be garbage collected to be cleaned up.
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