Bug 3408 - Behaviour of string.Trim differs from Microsoft.NET 4.0
Summary: Behaviour of string.Trim differs from Microsoft.NET 4.0
Alias: None
Product: Class Libraries
Classification: Mono
Component: mscorlib ()
Version: 2.10.x
Hardware: PC Linux
: --- normal
Target Milestone: Untriaged
Assignee: Bugzilla
Depends on:
Reported: 2012-02-11 12:17 UTC by Jon Siddle
Modified: 2012-02-14 11:06 UTC (History)
2 users (show)

Is this bug a regression?: ---
Last known good build:

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Description Jon Siddle 2012-02-11 12:17:26 UTC
.NET 4.0 changed the behaviour of string.Trim() from using an internal list of which characters count as whitespace to using the Unicode definition. For example, the BOM codepoint is trimmed under .NET 3.5 but not .NET 4.0.

The following code demonstrates the difference:


This will evaluate to 0 on .NET 3.5 and to 1 on .NET 4.0.

Mono (2.10 using dmcs to compile) seems to incorrectly evaluate this to 0.
Comment 1 Marek Safar 2012-02-14 11:06:13 UTC
Fixed in master.