如何将美国格式的数字字符串转换为欧洲格式的数字字符串？

I am working on a WPF application such that on the UI there is a combo-box that allows the user to select a culture from a drop down list, then on the basis of which culture the user selects I want to convert a numeric string in the existing culture to the one that the user selects from the combo-box. For instance - 2,325,655.65 (US format) vs. 2.325.655,65 (European format). I am working on a WPF application such that on