Do...Loop 语句

Repeats the statements between the Do and the Loop statement while the condition is True or until the condition becomes True.

语法:

Do statement

Do {While | Until} condition = True
' Do While: The statement block is repeated as long as the condition is true
' Do Until: The statement block is repeated as long as the condition is false
   statements
   [Exit Do]
   statements
Loop

Do...Loop statement

Do
   statements
   [Exit Do]
   statements
' Loop While: The statement block repeats as long as the condition is true
' Loop Until: The statement block repeats until the condition is true
Loop {While | Until} condition = True

参数:

The Do...Loop statement executes a loop as long as, or until, a certain condition is True. The condition for exiting the loop must be entered following either the Do or the Loop statement. The above examples are valid combinations.

condition: A comparison, numeric or Basic expression, that evaluates to either True or False.

statements: Statements that you want to repeat while or until a condition is True.

「Exit Do」语句可用于无条件地结束循环。您可以在「Do...Loop」语句中的任意位置加入此语句。此外，也可以使用「If...Then」结构定义一个退出条件:

Do...
   statements
   If condition = True Then Exit Do
   statements
Loop...

示例:

Sub ExampleDoLoop
    Dim sFile As String
    Dim sPath As String
    sPath = "c:\"
    sFile = Dir$( sPath ,22)
    If sFile <> "" Then
        Do
            MsgBox sFile
            sFile = Dir$
        Loop Until sFile = ""
    End If
End Sub

For, Select Case or While statements

Iif or Switch functions