Enterprise Library Test Guide - Willy .Net

162
Enterprise Library Test Guide
Test case
Verify that the application block
handles strings as entire strings instead
of as a series of characters.
This is especially important when
sorting or searching for substrings.
When the application block must
parse individual characters, verify
that the application block uses the
.NET Framework StringInfo class to
parse the individual text elements.
Verify that strings that the application
block stores internally (the end
user cannot see them) are stored in
a culture-independent format.
Verify that the application block’s
buffers are large enough to hold
translated strings. Translated
strings are often longer than the
original strings. For example, when
you translate strings from English
to German, the German strings are
longer than the English strings.
Verify that the application block
uses culture-independent operations
to compare strings such as
file names, persistence formats, or
symbolic information that the end
user does not see.
Example
The StringInfo class contains methods that retrieve individual
text elements from a given string. A text element
can be a base character, a surrogate pair, or a combined
character sequence. In the following example, the application
block retrieves individual text elements from a string
and displays them on the console.
TextElementEnumerator charEnum = StringInfo.
GetTextElementEnumerator(s);
while (charEnum.MoveNext())
{
Console.WriteLine(charEnum.GetTextElement());
Console.WriteLine(Environment.NewLine);
}
By storing strings in a culture-independent format, you can
ensure that processes that require culture-independent
results behave consistently, regardless of the actual culture.
Use the .NET Framework CultureInfo.InvariantCulture
property with strings that are culture-independent. This is
shown in the following example.
CultureInfo Invc = CultureInfo.InvariantCulture;
Thread.CurrentThread.CurrentCulture = Invc
In the following example, the application block reads an
array of 10 characters from a file. This may result in lost
data if the number of characters in the file for a local
language is larger than the number of characters used in
English.
char[] buffer = new char[10];
using (FileStream fs = new FileStream("", File-
Mode.Open))
{
using (StreamReader sr = new StreamReader(fs))
{
sr.Read(buffer, 0, 10);
}
}
If an application block uses a comparison operation to determine
if a string is a recognized XML tag, that comparison
should be culture-independent. If the application block
bases a security decision on the result of a string comparison
or case change operation, the operation should
be culture-independent to ensure that the result is not
affected by the value of the CultureInfo.CurrentCulture
property. To make the comparison culture independent,
use the overload of the .NET Framework String.Compare
method that takes a CultureInfo object as a parameter.
Pass in the CultureInfo.InvariantCulture property, This is
shown in the following example.
int compareResult = String.Compare(string1,
string2, false, CultureInfo.InvariantCulture);