Once you have your string in a double/decimal to get it into the correct formatting for a specific locale use
double amount = 1234.95;
amount.ToString("C") // whatever the executing computer thinks is the right fomat
amount.ToString("C", System.Globalization.CultureInfo.GetCultureInfo("en-ie")) // €1,234.95
amount.ToString("C", System.Globalization.CultureInfo.GetCultureInfo("es-es")) // 1.234,95 €
amount.ToString("C", System.Globalization.CultureInfo.GetCultureInfo("en-GB")) // £1,234.95
amount.ToString("C", System.Globalization.CultureInfo.GetCultureInfo("en-au")) // $1,234.95
amount.ToString("C", System.Globalization.CultureInfo.GetCultureInfo("en-us")) // $1,234.95
amount.ToString("C", System.Globalization.CultureInfo.GetCultureInfo("en-ca")) // $1,234.95