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c# - 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

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.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

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