Question

我正在尝试执行以下操作：

显示供用户输入的选项列表。所有用户输入选择都是整数（在这种情况下为1、2、3、4和5）如果用户输入有效选项之一，则应在屏幕上回显他们的输入。如果用户输入大于给定的选项，则应向用户显示一条消息，即他们的输入大于允许的选项。如果用户输入的值低于给定的选项，则应向用户显示一条消息，即他们的输入值低于允许的选项。如果用户输入的不是整数，则应向他们显示一条消息，指出他们的输入不是有效数字。如果用户输入为空，则应显示一条消息，说明其输入不能为空。然后，当然，如果出现上面未定义的其他错误，应该告诉他们存在未知错误。

这是我所拥有的，并且大多数情况下都有效。...

cls
echo "What computers are we working on?"
echo ""
echo "1 = All Computer Lab Computers"
echo "2 = Watts' Computer Lab Computers"
echo "3 = Wells' Computer Lab Computers"
echo "4 = A Specific Computer"
echo "5 = Custom list of Computer Lab Computers"
echo ""
echo ""
$empty = $null
$result = $null
[int]$result = read-host "Make a Selection (1 - 5) "
cls
Clear-Host
IF ( $result -lt "6" -and $result -gt "0" ) { echo " You Selected $result" }
ElseIf ( $result -ge "6") {echo "Your Selection of $result was greater than 
allowed options" }
ElseIf ( $result -le "0" ) {echo "Your Selection of $result was smaller than 
allowed options" }
ElseIf ( $result -eq "") {echo "Your input cannot be blank!" }
ElseIf ( $result -isNot ([int]) ) {echo " Your Selection of $result is not a 
valid number. Please try again."}
Else { echo "No clue what happened...but you chose $result"}

但是，如果用户输入非整数或将输入留为空白，则它不会显示预期的消息，而是显示低于允许选项的用户输入消息。即使用户没有输入任何内容，它也会返回用户输入为“ 0”的

关于如何使这项工作达到预期的任何想法吗？

Answer 1

这是执行文本菜单的另一种方法... [咧嘴]

$MenuList = @(
    'All Computer Lab Computers'
    'Watts Computer Lab Computers'
    'Wells Computer Lab Computers'
    'A Specific Computer'
    'Custom list of Computer Lab Computers'
    )

$MenuTitle = 'What computers are we working on?'

$ValidChoices = 1..($MenuList.Count)

$Choice = ''
while ([string]::IsNullOrEmpty($Choice))
    {
    Clear-Host
    Write-Host $MenuTitle
    foreach ($ML_Item in $MenuList)
        {
        Write-Host ('    {0} - {1}' -f ($MenuList.IndexOf($ML_Item) + 1), $ML_Item)
        }
    $Choice = Read-Host 'Please select an item from the above list by number or [ x ] to exit '
    Write-Host ''

    if ($Choice -eq 'x')
        {
        Write-Host 'Exiting now ...'
        break
        }
    if ($Choice -notin $ValidChoices)
        {
        [console]::Beep(1000, 300)
        Write-Warning ('    Your selection [ {0} ] is not valid.' -f $Choice)
        Write-Warning '    Please try again ...'
        pause
        $Choice = ''
        }
    }

''
'You chose [ {0} ]' -f $Choice

菜单显示...

What computers are we working on?
    1 - All Computer Lab Computers
    2 - Watts Computer Lab Computers
    3 - Wells Computer Lab Computers
    4 - A Specific Computer
    5 - Custom list of Computer Lab Computers
Please select an item from the above list by number or [ x ] to exit :

输出无效输入...

WARNING:     Your selection [ r ] is not valid.
WARNING:     Please try again ...
Press Enter to continue...:

有效输入2 ...

的输出

You chose [ 2 ]

Answer 2

您可以使用do / until和try / catch使其更加简化，这也将消除对所有if语句的需求

cls
$menu = "What computers are we working on?
1 = All Computer Lab Computers
2 = Watts' Computer Lab Computers
3 = Wells' Computer Lab Computers
4 = A Specific Computer
5 = Custom list of Computer Lab Computers

"
echo $menu
$result = $null

do {
    try {
        $isValid = $true
        [int]$result = read-host "Make a Selection (1 - 5) "
    }
    catch {$isValid = $false}
        Clear-Host
        echo "Your Selection of $result is not a valid number. Please try again"
        echo ""
        echo $menu
    } # end do 
until (($result -lt 6 -and $result -gt 0) -and $isValid)

cls
Clear-Host
echo " You Selected $result"

使用Powershell，如果用户输入的数字不是数字或不是给定的选项之一，则显示自定义消息

2 个答案: