What's wrong with my usage of String.EndsWith?

Question

I can't figure out why EndsWith is returning false.

I have the C# code:

string heading = "yakobusho";
bool test = (heading == "yakobusho");
bool back = heading.EndsWith("sho");
bool front = heading.StartsWith("yak");
bool other = "yakobusho".EndsWith("sho");
Debug.WriteLine("heading = " + heading);
Debug.WriteLine("test = " + test.ToString());
Debug.WriteLine("back = " + back.ToString());
Debug.WriteLine("front = " + front.ToString());
Debug.WriteLine("other = " + other.ToString());

The output is:

heading = yakobusho
test = True
back = False
front = True
other = True

What is going on with EndsWith?

Copying this out into [dotnetfiddle](https://dotnetfiddle.net/j3SEY3) highlights the fact that there's a hidden character at the beginning of `"sho"` — Diado, Mar 07 '19 at 14:34
Different characters, possibly a hidden character. There's nothing wrong with `EndsWith()` — Panagiotis Kanavos, Mar 07 '19 at 14:34

score 4 · Answer 1 · answered Mar 07 '19 at 14:35

4

This contains an invisible character before the "sho" string:

bool back = heading.EndsWith("sho");

The corrected line:

bool back = heading.EndsWith("sho");

answered Mar 07 '19 at 14:35

Tor

633
5
14

score 1 · Accepted Answer · answered Mar 07 '19 at 14:42

The "sho" string in the third line starts with a zero length space. "sho".Length returns 4 while ((int)"sho"[0]) returns 8203, the Unicode value of the zero length space.

You can type it in a string using its hex code, eg :

"\x200Bsho"

Annoyingly, that character isn't considered whitespace so it can't be removed with String.Trim().

score 0 · Answer 3 · answered Mar 07 '19 at 14:46

In your EndsWith argument there is a special character.

As you can see from this code:

  class Program
  {
    static void Main(string[] args)
    {
      string heading = "yakobusho";

      string yourText = "sho";
      bool back = heading.EndsWith(yourText);

      Debug.WriteLine("back = " + back.ToString());
      Debug.WriteLine("yourText length = " + yourText.Length);

      string newText = "sho";
      bool backNew = heading.EndsWith(newText);

      Debug.WriteLine("backNew = " + backNew.ToString());
      Debug.WriteLine("newText length = " + newText.Length);

    }
  }

OUTPUT:

back = False
yourText length = 4
backNew = True
newText length = 3

The length of yourText is 4 and so there is some hidden character in this string.

Hope this helps.

What's wrong with my usage of String.EndsWith?

3 Answers3