Conditionally suspends execution at the line on which the method appears.

Syntax

object.Assert booleanexpression

The Assert method syntax has the following object qualifier and argument:

Part Description
object Required. Always the Debug object.
booleanexpression Required. An expression that evaluates to either True or False.

Remarks

Assert invocations work only within the development environment. When the module is compiled into an executable, the method calls on the Debug object are omitted.

All of booleanexpression is always evaluated. For example, even if the first part of an And expression evaluates False, the entire expression is evaluated.

Example

The following example shows how to use the Assert method. The example requires a form with two button controls on it. The default button names are Command1 and Command2.

When the example runs, clicking the Command1 button toggles the text on the button between 0 and 1. Clicking Command2 either does nothing or causes an assertion, depending on the value displayed on Command1. The assertion stops execution with the last statement executed, the Debug.Assert line, highlighted. 

Option Explicit Private blnAssert As Boolean Private intNumber As Integer Private Sub Command1_Click() blnAssert = Not blnAssert intNumber = IIf(intNumber <> 0, 0, 1) Command1.Caption = intNumber End Sub Private Sub Command2_Click() Debug.Assert blnAssert End Sub Private Sub Form_Load() Command1.Caption = intNumber Command2.Caption = "Assert Tester" End Sub