If...Then...Else Statement

Defines one or more statement blocks that you only want to execute if a given condition or expression is True.

  If condition Then 
      statements
  [{ElseIf|Else If} expression Then
      statements]
  [Else 
      statements]
  {EndIf|End If}

Instead of Else If you can write ElseIf, instead of End If you can write EndIf.

If statements can be shortened to one line when using single statement blocks.

  If condition Then statement [Else statement]

The If...Then statement executes program blocks depending on given conditions. When LibreOffice Basic encounters an If statement, the condition is tested. If the condition is True, all subsequent statements up to the next Else or ElseIf statement are executed. If the condition is False, and an ElseIf statement follows, LibreOffice Basic tests the next expression and executes the following statements if the condition is True. If False, the program continues either with the next ElseIf or Else statement. Statements following Else are executed only if none of the previously tested conditions were True. After all conditions are evaluated, and the corresponding statements executed, the program continues with the statement following EndIf.

If...Then ステートメントは、複数のものをネスト (入れ子化) することができます。

Else および ElseIf は省略可能です。

GoTo や GoSub を使って、If...Then の中から外へジャンプすることは可能ですが、If...Then の中にジャンプすることはできません。

下記の例では、製品の有効期限をユーザーに入力させて、期限が切れていないかを判定しています。

Sub ExampleIfThenDate
    Dim sDate As String
    Dim sToday As String
    sDate = InputBox("Enter the expiration date (MM.DD.YYYY)")
    sDate = Right$(sDate, 4) + Mid$(sDate, 4, 2) + Left$(sDate, 2)
    sToday = Date$
    sToday = Right$(sToday, 4)+ Mid$(sToday, 4, 2) + Left$(sToday, 2)
    If sDate < sToday Then
        MsgBox "The expiration date has passed"
    ElseIf sDate > sToday Then
        MsgBox "The expiration date has not yet passed"
    Else
        MsgBox "The expiration date is today"
    End If
End Sub