Get Substring - everything before certain char

I'm trying to figure out the best way to get everything before the - character in a string. Some example strings are below. The length of the string before - varies and can be any length

223232-1.jpg
443-2.jpg
34443553-5.jpg

so I need the value that's from the start index of 0 to right before -. So the substrings would turn out to be 223232, 443, and 34443553

.Net Fiddle example

class Program
{
    static void Main(string[] args)
    {
        Console.WriteLine("223232-1.jpg".GetUntilOrEmpty());
        Console.WriteLine("443-2.jpg".GetUntilOrEmpty());
        Console.WriteLine("34443553-5.jpg".GetUntilOrEmpty());

        Console.ReadKey();
    }
}

static class Helper
{
    public static string GetUntilOrEmpty(this string text, string stopAt = "-")
    {
        if (!String.IsNullOrWhiteSpace(text))
        {
            int charLocation = text.IndexOf(stopAt, StringComparison.Ordinal);

            if (charLocation > 0)
            {
                return text.Substring(0, charLocation);
            }
        }

        return String.Empty;
    }
}

Results:

223232
443
34443553
344

34

Use the split function.

static void Main(string[] args)
{
    string s = "223232-1.jpg";
    Console.WriteLine(s.Split('-')[0]);
    s = "443-2.jpg";
    Console.WriteLine(s.Split('-')[0]);
    s = "34443553-5.jpg";
    Console.WriteLine(s.Split('-')[0]);

Console.ReadKey();
}

If your string doesn't have a - then you'll get the whole string.

String str = "223232-1.jpg"
int index = str.IndexOf('-');
if(index > 0) {
    return str.Substring(0, index)
}

Things have moved on a bit since this thread started.

Now, you could use

string.Concat(s.TakeWhile((c) => c != '-'));

One way to do this is to use String.Substring together with String.IndexOf:

int index = str.IndexOf('-');
string sub;
if (index >= 0)
{
    sub = str.Substring(0, index);
}
else
{
    sub = ... // handle strings without the dash
}

Starting at position 0, return all text up to, but not including, the dash.