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發表者： 冷日 發表時間： 2015/12/21 10:06:27
PowerShell Comparison Operators
The following operators are all Case-Insensitive by default:
To perform a Case-Sensitive comparison just prefix any of the above with "c"
for example -ceq for case-sensitive Equals or -creplace for case-sensitive replace.
Similarly prefixing with "i" will explicitly make the operator case insensitive.
Types
Logical operators
Bitwise operators
Format Operator
The format_string is in the form: {0,-5} {1,-20} {2,-10}
In each set of braces, the first number, before the comma refers to the column.
The second number, after the comma determines the padding (how many characters)
If the second number is negative, it not only pads the element, but aligns it vertically. Optionally the second number can be used for formatting :hh :mm :C :p
Examples
原文出處：Comparison operators | PowerShell | SS64.com
The following operators are all Case-Insensitive by default:
-eq Equal
-ne Not equal
-ge Greater than or equal
-gt Greater than
-lt Less than
-le Less than or equal
-like Wildcard comparison
-notlike Wildcard comparison
-match Regular expression comparison
-notmatch Regular expression comparison
-replace Replace operator
-contains Containment operator
-notcontains Containment operator
-shl Shift bits left (PowerShell 3.0)
-shr Shift bits right – preserves sign for signed values.(PowerShell 3.0)
-in Like –contains, but with the operands reversed.(PowerShell 3.0)
-notin Like –notcontains, but with the operands reversed.(PowerShell 3.0)
To perform a Case-Sensitive comparison just prefix any of the above with "c"
for example -ceq for case-sensitive Equals or -creplace for case-sensitive replace.
Similarly prefixing with "i" will explicitly make the operator case insensitive.
Types
-is Is of a type
-isnot Is not of a type
-as As a type, no error if conversion fails
Logical operators
-and Logical And
-or Logical Or
-not logical not
! logical not
Bitwise operators
-band Bitwise and
-bor Bitwise or
Format Operator
"format_string" -f Object1, Object2,...
The format_string is in the form: {0,-5} {1,-20} {2,-10}
In each set of braces, the first number, before the comma refers to the column.
The second number, after the comma determines the padding (how many characters)
If the second number is negative, it not only pads the element, but aligns it vertically. Optionally the second number can be used for formatting :hh :mm :C :p
Examples
$demo = $null
if (-Not ($demo)) { write "Zero, null or Empty"}
if (!($demo)) { write "Zero, null or Empty"}
$myVar -is "String"
$myVar -eq 123
$myVar -ceq $myVar2
"abcdef" -like "abc*"
"abcdef" -replace "dEf","xyz"
$myVar1 -is "String" -and $myVar2 -is "Int"
"{2:N}" -f 24.4567
(1 -eq 1) -and -not (2 -gt 2)
$mycmd = ps | select id,ProcessName
foreach ($proc in $mycmd) {"{0,-8}{1,-20}" -f $proc.id, $proc.ProcessName}
原文出處：Comparison operators | PowerShell | SS64.com