Returns a Boolean value indicating whether an expression (expression: Any combination of mathematical or logical operators, constants, functions, and names of fields, controls, and properties that evaluates to a single value. Expressions can perform calculations, manipulate characters, or test data.)> is an error value.
Syntax
IsError(expression)
The required expression argument (argument: A value that provides information to an action, an event, a method, a property, a function, or a procedure.) can be any valid expression.
Remarks
Error values are created by converting real numbers to error values using the CVErr function. The IsError function is used to determine if a numeric expression (numeric expression: Any expression that evaluates to a number. The expression can be any combination of variables, constants, functions, and operators.) represents an error. IsError returns True if the expression argument indicates an error; otherwise, it returns False.
Example
Note Examples that follow demonstrate the use of this function in a Visual Basic for Applications (VBA) module. For more information about working with VBA, select Developer Reference in the drop-down list next to Search and enter one or more terms in the search box.
This example uses the
IsError function to check if a numeric expression is an error value. The
CVErr function is used to return an
Error Variant from a user-defined function. Assume
UserFunction is a user-defined function procedure that returns an error value; for example, a return value assigned with the statement
UserFunction = CVErr(32767), where 32767 is a user-defined number.
Dim ReturnVal, MyCheck
ReturnVal = UserFunction()
MyCheck = ReturnVal ' Returns True.
