`String.Length` bug?

Am I misunderstanding something here? I’m writing a complex medical imaging parser and have hit a bug.

Run this code:

Var s As String = "1.2.840.10008.1.​2.​1"
Var sLen As Integer = s.Length
// sLen should be 19 but is reported as being 21.

Why is sLen 21 and not 19? Unless I am miscounting, there are 19 characters in 1.2.840.10008.1.​2.​1

Not only do I think this is a bug but it’s propagating throughout my code as String comparisons are failing.

What does the text look like in the debugger?

Debugger 1

There is some unknown character in the string. I also tried and got length as 21. but i cleared the value and manually typed the characters and got length as 19.

Use this :
Var s As String = “1.2.840.10008.1.2.1”

You’ve got a:

U+200B ​ e2 80 8b ZERO WIDTH SPACE

in there.

In fact two of them.

So no bug, you have a bad string.


Dang - you guys are right.

What seems to have happened is that I cut and pasted several dozen strings and put them as constants in a class. I copied them from a website but there must have been some non-visible characters in them.

What a pain.

Thank you.

The IDE has a command somewhere to get rid of non-ASCII stuff - I’ve never used it but I’ve heard it mentioned on the forums a few times.

I find this website to be handy when looking to see what an odd sequence of possible UTF8 bytes corresponds to:


Right-click in the text editor to see the option.

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Holy smoke - what great a find!

Would be nice if that existed in the text area you enter constants into…