Question

I have a collection of key/values in the form of a Dictionary<string, string>.

How would you convert or aggregate this into an attribute string:

key1="value1" key2="value2" key3="value3"

I believe this can be achieved using Aggregate function, however, I find the documentation on this particular extension method confusing. Any help is much appreciated.

Answer 1

I’d use:

.NET 4:

var text = string.Join(" ", 
              dictionary.Select(pair => string.Format("{0}={1}",
                                pair.Key, pair.Value));

.NET 3.5 (where string.Join has fewer overloads)

var text = string.Join(" ", 
              dictionary.Select(pair => string.Format("{0}={1}",
                                pair.Key, pair.Value)
                        .ToArray());

If you need to do any escaping, do it in the string.Format call. Of course, you don’t need to use string.Format – you could use:

var text = string.Join(" ", dict.Select(pair => pair.Key + "=" + pair.Value));

It depends on which you find more readable. (The performance difference will be negligible.)