Datasheet

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CHAPTER 1 VISUAL STUDIO 2010

static VariableName string, which is acting as a placeholder. Once you have entered the variable name you want,

you can just press Tab. At that point the editor automatically jumps to the next highlighted item. This capability

to insert a block of boilerplate code and have it automatically respond to your customization is extremely useful.

Code expansion enables you to quickly shift between the values that need to be customized, but these values

are also linked where appropriate, as in the next example. Another code expansion shortcut creates a new

property in a class. If at the class level you type the letters “ prop ” and then press the Tab key twice, after the

ﬁ rst tab you ’ ll ﬁ nd that your letters become the word “ Property ” ; and after the second tab the code shown in

Figure 1 - 19 will be added to your existing code. On the surface this code is similar to what you see when you

expand the

Select statement. Note that although you type prop , even the internal value is part of this code

expansion. Furthermore, although Visual Basic implemented a property syntax that is no longer dependent on

an explicit backing ﬁ eld, this expansion provides the more robust syntax that uses an explicit backing ﬁ eld.

FIGURE 1 - 19

The difference, however, is that the same value String in Figure 1 - 19 is repeated for the property. The value

you see is the default. However, when you change the ﬁ rst such entry from String to Integer , Visual Studio

automatically updates all three locations because it knows they are linked. Using the code shown in Figure 1 - 19,

update the property value to be

m_Count . Press Tab and change the type to Integer ; press Tab again and label

the new property

Count . This gives you a simple property on this form for use later when debugging.

The completed code should look like the following block:

Private m_Count As Integer

Public Property Count() As Integer

Get

Return m_Count

End Get

Set(ByVal value As Integer)

m_Count = value

End Set

End Property

Code snippet from Form1

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