Question

What is the tersest way to transform an integer array into a string enumerating the elements inline? I’m thinking something like an anonymous function that performs the conversion.

var array = new int[] { 1, 2 }
var s = string.Format("{0}", 
                      new [] 
                      { /*inline transform array into the string "1, 2"*/ });

Answer 1

Use string.Join. In .NET 3.5 and earlier you need to convert to a string array first; in .NET 4 there’s an overload taking IEnumerable<T>. So depending on your version:

.NET 2.0 or 3.0 / C# 2:

string s = string.Join(", ",
    Array.ConvertAll(delegate(int x) { return x.ToString(); });

.NET 2.0 or 3.0 / C# 3:

string s = string.Join(", ", Array.ConvertAll(x => x.ToString());

.NET 3.5 / C# 3:

string s = string.Join(", ", array.Select(x => x.ToString()).ToArray());

(or use the version which works with .NET 2.0 if you prefer).

.NET 4:

string s = string.Join(", ", array);

(I hadn’t even seen that before today!)