VB6 Format equivalent in C#
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I am converting some VB6 code to C# and am having a problem duplicating certain functionality. I have a string representation of a number ex.6000 and a format specifier of ex. ###0.000.

VB6 Example:

    Format(number, "########0.000") = "6.000"

I am having trouble finding the C# equivalent to duplicate this functionality. The methods I have tried with `ToString()` but they are more for formatting the actual number rather than more of an overlay format like VB6 is doing.

C# Example:

    number.ToString("########0.000", CultureInfo.InvariantCulture) = 6000.000