StringBuilder.Append Method (Single)
Appends the string representation of a specified single-precision floating-point number to this instance.
Assembly: mscorlib (in mscorlib.dll)
The method modifies the existing instance of this class; it does not return a new class instance. Because of this, you can call a method or property on the existing reference and you do not have to assign the return value to a StringBuilder object, as the following example illustrates.
The capacity of this instance is adjusted as needed.Notes to Callers
In the .NET Framework 4, when you instantiate the StringBuilder object by calling the StringBuilder constructor, both the length and the capacity of the StringBuilder instance can grow beyond the value of its MaxCapacity property. This can occur particularly when you call the Append and AppendFormat methods to append small strings.