string.Join on a List or other type

Question

I want to turn an array or list of ints into a comma delimited string, like this:

string myFunction(List a) {
    return string.Join(\",\", a);
}
         


        

Answer 1

This answer is for you if you don't want to venture into the depths of .NET 4.0 just yet.

String.Join() concatenates all the elements of a string array, using the specified separator between each element.

The syntax is

public static string Join(
    string separator,
    params string[] value
)

Rather than passing your List of ints to the Join method, I suggest building up an array of strings first.

Here is what I propose:

static string myFunction(List a) {
    int[] intArray = a.ToArray();
    string[] stringArray = new string[intArray.Length];

    for (int i = 0; i < intArray.Length; i++)
    {
        stringArray[i] = intArray[i].ToString();
    }

    return string.Join(",", stringArray);
}