Microsoft KB Archive/129287

= INFO: Differences Between Exclamation Mark (!) & Dot (.) Syntax =

Article ID: 129287

Article Last Modified on 12/9/2003

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APPLIES TO


 * Microsoft Visual Basic 4.0 Standard Edition
 * Microsoft Visual Basic 4.0 Professional Edition
 * Microsoft Visual Basic 4.0 Professional Edition
 * Microsoft Visual Basic 4.0 16-bit Enterprise Edition
 * Microsoft Visual Basic 4.0 32-Bit Enterprise Edition

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This article was previously published under Q129287





SUMMARY
In Visual Basic version 4.0, the exclamation mark (!) syntax is for collection lookup, and the dot (.) syntax is for properties and methods.

However, a control can be accessed as a property, and Visual Basic has a Controls collection on a form. Because the Controls collection is the default property of a form, you can access a control from a Form using by using the exclamation mark (!) syntax.



MORE INFORMATION
To obtain direct access to the Ctrl1 property on the form, type this: Form1.Ctrl1.Text = "Hello" This line: Form1!Ctrl1.Text = "Hello" translates into this code: Form1.Controls.Item("Ctrl1").Text = "Hello" Visual Basic for Applications has a specific optimization for Forms that allows the compiler to translate this syntax: Form1!Ctrl1.Text = "Hello" into this code: Form1.Ctrl1.Text = "Hello" Therefore the performance of the two statements should be identical. Note that this optimization is specific to controls on Visual Basic version 4.0 forms. It will not work with any other collection.

WARNING: This optimization may not occur in future versions of Visual Basic forms.

Steps to Reproduce Behavior in Visual Basic 4.0
 Create a new project, and add a CommandButton to Form1.  Double-click Form1 to edit the Form_Load event, and type: Form1!Command1.Caption = "Test" Form1.Command1.Caption = "It Works!"  Run the project, and notice how both methods work.

Additional query words: bang

Keywords: kbinfo KB129287

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