Today just quick tip about StringBuilder I used to remove last character(s) from StringBuilder using Remove method.

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 StringBuilder builder = new StringBuilder("some long text with comma,");
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 builder.Remove(builder.Length - 1, 1);

However, recently I’ve came accross even simpler solution. You just need to lessen the Length property of StringBuilder, in order to get rid of last characters

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StringBuilder builder = new StringBuilder("some long text with comma,");
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builder.Length--;