substring from specific point of the string(from reverse side )

I wanted to substring from special point.

abcdef.png

I want

.png

Here i tried

    string str = "abcdef.png";
    str = str.Substring(0, str.Length - 4);

but then only shows the abcdef only BUT i want .png part

Jon Skeet
people
quotationmark

Just use the overload which takes a single parameter - the start point:

str = str.Substring(str.Length - 4);

Or better, use a method designed to get the extension of a filename - Path.GetExtension:

string extension = Path.GetExtension(str);

people

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