Formatting Large Numbers with .NET

Question

I have a requirement to format large numbers like 4,316,000 as \"4.3m\".

How can I do this in C#?

Answer 1

long valueToFormat = 4316000;
var dict = new Dictionary() {
    {1000000000, "b"},
    {1000000, "m"},
    {1000, "k"}
 };

 string formattedValue = valueToFormat.ToString();
 foreach (long n in dict.Keys.OrderBy(k => k)) {
     if (valueToFormat < n) {
         continue;
     }
     double value = Math.Round(valueToFormat / (double)n, 1);
     formattedValue = String.Format("{0}{1}", value, dict[n]);
 }
 Console.WriteLine(formattedValue);