Newer StringBuilder? How to set String to null safely?

I see that String and StringBuilder in C# / C++ do not have an easy
way to set a string to null or zero length, once it is instantiated.

>I see that String and StringBuilder in C# / C++ do not have an easy
way to set a string to null or zero length, once it is instantiated.

StringBuilder myString = new StringBuilder("Hello");
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myString.Append(" World!");

myString = null; //the intent here is to reset the string to a "" or
zero length string; obviously this is not the way to do this, as you
get a run-time error

I see that String and StringBuilder in C# / C++ do not have an easy
way to set a string to null or zero length, once it is instantiated.
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Apparently some variant of the .NET languages do (reading between the
lines from another fragment I found).
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So the problem is to do this quickly (of course it can be done in a
roundabout manner), using either StringBuilder or String. I'm using
C#.NET version 2.0 (Visual Studio 2005). It looks like possibly
there's a new string class introduced in version 3.0 that has
a .remove or .clear public method?!
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Ray Lopez
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//////////////////// start
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StringBuilder myString = new StringBuilder("Hello");
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myString.Append(" World!");
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Console.WriteLine("write out your string: {0}", myString); //Hello
World!
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myString = null; //the intent here is to reset the string to a "" or
zero length string; obviously this is not the way to do this, as you
get a run-time error
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Console.WriteLine(myString==null); // you get output: "True", since
myString is now null.
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// this next line won't work--gives a runtime error, so the question
is: how to reset your string?
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// myString.Append("my new string text for myString here, but gives a
runtime error!");
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//////////////////// end
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Perhaps not the appropriate group. You should likely try a C# group instead
such as microsoft.public.dotnet.languages.csharp
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In addtion to creating a new stringbuilder, it looks like myString.Length=0
should work according to the documentation (myString being actually a
StringBuilder object).
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