如何從 powershell 中的字符串中獲取十進制數？

Question

1. 我有一個包含十進制值的字符串（例如'good1432.28morning to you' ）
2. 我需要從字符串中提取1432.28並將其轉換為十進制

Answer 1

這可以通過多種方式完成，在 stackoverflow 中找不到完全相似的問題/解決方案，所以這里有一個對我有用的快速解決方案。

Function get-Decimal-From-String 
{
    # Function receives string containing decimal
 param([String]$myString)

    # Will keep only decimal - can be extended / modified for special needs
$myString = $myString -replace "[^\d*\.?\d*$/]" , ''

    # Convert to Decimal 
[Decimal]$myString

}

撥打電話 Function

$x = get-Decimal-From-String 'good1432.28morning to you'

結果

1432.28

Answer 2

其他解決方案：

-join ('good143.28morning to you' -split '' | where {$_ -ge '0' -and $_ -le '9' -or $_ -eq '.'})

Answer 3

另一種選擇：

function Get-Decimal-From-String {
    # Function receives string containing decimal
    param([String]$myString)

    if ($myString -match '(\d+(?:\.\d+)?)') { [decimal]$matches[1] } else { [decimal]::Zero }
}

正則表達式詳細信息

(               Match the regular expression below and capture its match into backreference number 1
   \d           Match a single digit 0..9
      +         Between one and unlimited times, as many times as possible, giving back as needed (greedy)
   (?:          Match the regular expression below
      \.        Match the character “.” literally
      \d        Match a single digit 0..9
         +      Between one and unlimited times, as many times as possible, giving back as needed (greedy)
   )?           Between zero and one times, as many times as possible, giving back as needed (greedy)
)

Answer 4

("good1432.28morning to you" -split "\.")[1]

(1557.18 -split "\.")[1]