c# change specific character string
String str = "1 2 3 4 5 6 7 8 9";
Console.WriteLine("Original string: \"{0}\"", str);
Console.WriteLine("CSV string: \"{0}\"", str.Replace(' ', ','));
// This example produces the following output:
// Original string: "1 2 3 4 5 6 7 8 9"
// CSV string: "1,2,3,4,5,6,7,8,9"