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has wineglasses from Pier 1。 If you use the Equals（） method to pare the boxes； it will return
False； because the box content details are not identical。 The difference lies in how the glasses
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are described。 In contrast； calling GetHashCode（） will indicate that the contents of the boxes are
identical。 This is because GetHashCode（） is doing a quick contents identification。
The difference between the Equals（） and GetHashCode（） methods is perspective。 In the
example； from the perspective of the moving pany； the boxes are identical because the
moving pany does not care whether the wineglasses are from IKEA or Pier 1； it will not
distinguish wineglasses from different panies。
The fact that GetHashCode（） can return identical numbers for what would seem dissimilar
object contents can confuse developers。 The way to understand GetHashCode（） is that； rather
than being useful to verify equality； it helps you verify inequality。 If two objects return dissim
ilar hash code values； then you know the contents are not identical。 The intent of a hash code
is to generate a quick fingerprint of the contents of an object。 It is not pletely reliable； but
works for the most part。
WHEN INTELLISENSE IS NOT ENOUGH
IntelliSense is very good and will even display ments that explain what the method does （as illustrated in
Figure 3…2）。 Another place to find answers is the Microsoft documentation itself； which you can access by
selecting Help Index。 You can use the Look For box to search for a specific type。 For example； if you type
“String class” in the Look For box； you will see details of the String class； which you can then filter using the
links at the top of the page。
The Microsoft documentation is part of the Microsoft Developer Network （MSDN） （ http：//
msdn。microsoft。）。 The MSDN web site contains documentation that helps you figure out the stan
dard software development kit （ SDK） application programming interface （API）。 There are literally thou
sands of types； with an explosion of methods and properties。 You will definitely not use all of them in a single
application； but you will always use the SDK。
In most cases； MSDN will be enough to help you figure out when you don’t know about a specific type。
If you want to learn more about concepts； you can surf to a web site such as Code Project （http：//
codeproject。）。 Code Project contains plenty of examples for almost every development topic that
suits your fancy。
The Problem： Character…by…Character parison
Let’s get back to the bug of the whitespace。 The method that caused problems was pareTo（）。
Looking at the MSDN documentation； you see the following definition for this method （found
by scrolling down the String class page and clicking the pareTo link）：
pares this instance with a specified Object。
This definition does not tell you much； so you will need to go back to the String page and
click another method name。 Click the pare link； and then click the pare（String； String）
link。 In the explanation of the pare（） method； you find the following text：
The parison terminates when an inequality is discovered or both strings have been
pared。 However； if the two strings pare equal to the end of one string； and the
other string has characters remaining； then the string with remaining characters is
considered greater。 The return value is the result of the last parison performed。
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■Note Looking up the meaning of a method is not a long process； even though it may seem like that from
the description in this section。 With experience； you don’t even notice the extra clicks。
The pareTo（） method failed because of the character…by…character parison； which
is illustrated in Figure 3…7。
Figure 3…7。 How pareTo（） fails to pare strings that appear identical but have extra
characters
Strings are stored in buffers； with one space in the buffer allocated to one character。 As you
can see from Figure 3…7； whitespace takes up one space in the buffer。 We can take advantage of
this sometimes； as you’ll see in the next section。
Now that you know what the problem is； the next step is to find a solution。
Solving the Extra Whitespace Problem
You can solve the whitespace problem in multiple ways。 Which way you use depends on your
needs。 Let’s look at several solutions and see which works best for our translation program。
Trimming the Whitespace
The first solution we’ll look at is to trim the whitespace using a method intended for that purpose。
The whitespace problem is not unique and is well known。 The String type has a method that
can be used to remove； or trim； the whitespace from a buffer。 You can remove whitespace at
the beginning； end； or both sides of the buffer。
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As tempting as it is to change the original implementation of TranslateHello（）； don’t do
that； because you might inadvertently break something that is working just fine。 When you
develop code； you have multiple possible ways to solve a problem。 If you start messing around
with the original source code； by the time you reach the third or fourth solution； the code might
be a plete mess。 Your fixes might make things worse； and trying to backtrack in your source
code bees very difficult。
■Note To manage your source code； you should use version control。 However； even with version control；
when you delete past attempts； ideas get lost。 Thus； while your source code will be clean； you might forget
something you did three or four hours ago。 Trust me； this happens； because developing source code is an
intensive thought process。
The solution is to create a shim that calls the TranslateHello（） method。 The shim is used
to fix the bug。 The following shim code is a temporary solution：
Public Function TrimmingWhitespace（ByVal buffer As String） As String
Return Translator。TranslateHello（buffer。Trim（））
End Function
TrimmingWhitespace（） is a method that trims whitespace from the string to be translated。
buffer。Trim is new functionality that preprocesses the buffer。 Finally； we call the original
method； TranslateHello（）； to perform the translation。
Of course； we need to test the new method to see if it trims the string to be translated。 The
following is the corresponding test code。
Dim verifyValue As String = TrimmingWhitespace（〃 allo〃）
If verifyValue。pareTo（〃hallo〃） 0 Then
Console。WriteLine（〃Extra white spaces allo to hallo test failed〃）
End If
The test calls the work…in…progress method； TrimmingWhitespace（）； to see if everything
works。 The verification code does not change。
So that you get predictable results； remember to call the shim and not the original method。
If you run the test code； you’ll see that the shim works； and thus we have a solution。
Finding a Substring
Another solution to the whitespace problem is to find a specific substring in a buffer。 Think of
it as a search solution； where a me