如何从 powershell 中的字符串中获取十进制数？

Question

1. I have a string containing a decimal value (eg 'good1432.28morning to you' )
2. I need to extract 1432.28 out of string and convert it to decimal

Answer 1

This can be done in many ways, could not find exact similar question / solution in stackoverflow, so here is a quick solution that worked for me .

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

}

Calling the Function

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

Result

1432.28

Answer 2

Other solution:

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

Answer 3

Another alternative:

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

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

Regex details

(               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]