Switch Function

Evaluates a list of expressions (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.) and returns a Variant value or an expression associated with the first expression in the list that is True.

Syntax

Switch(expr-1, value-1 [, expr-2, value-2 ] … [, expr-n, value-n ] )

The Switch function syntax has these arguments:

Argument Description
expr Required. Variant expression (variant expression: Any expression that can evaluate to numeric, string, or date data, as well as the special values Empty and Null.) you want to evaluate.
value Required. Value or expression to be returned if the corresponding expression is True.

Remarks

The Switch function argument (argument: A value that provides information to an action, an event, a method, a property, a function, or a procedure.) list consists of pairs of expressions and values. The expressions are evaluated from left to right, and the value associated with the first expression to evaluate to True is returned. If the parts aren't properly paired, a run-time error (run-time error: An error that can be detected only when an application is running.) occurs. For example, if expr-1 is True, Switch returns value-1. If expr-1 is False, but expr-2 is True, Switch returns value-2, and so on.

Switch returns a Null (Null: A value you can enter in a field or use in expressions or queries to indicate missing or unknown data. In Visual Basic, the Null keyword indicates a Null value. Some fields, such as primary key fields, can't contain a Null value.) value if:

  • None of the expressions is True.
  • The first True expression has a corresponding value that is Null.

Switch evaluates all of the expressions, even though it returns only one of them. For this reason, you should watch for undesirable side effects. For example, if the evaluation of any expression results in a division by zero error, an error occurs.

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 Switch function to return the name of a language that matches the name of a city.

Function MatchUp (CityName As String)
    Matchup = CityName = "London" "English" _
              CityName = "Rome" "Italian" _
              CityName = "Paris" "French"
End Function

      
 
 
Applies to:
Access 2007