Jump Start in PowerShell (Part II)

Introduction

Variables

• A variable in PowerShell starts with a $ sign (in the European Union with a € sign) and in the name can contain any letters, numbers and underscore.
• To assign a value to a variable, just assign it to it with the sign " = ". To display the value of a variable, you can simply write this variable. We will analyze the output of information in the text below.
  
  

  $var = 619
  $var
  

  
  
  
  
  
• Arithmetic operations can be performed on numbers, lines can be added. If you add a number to a string, the number is automatically converted to a string.
  
  

  $a = 1
  $b = 2
  $c = $a + $b
  $c   #c = 3
  $str = "Хабра"
  $str = $str + "хабр"
  $str   #str = Хабрахабр 
  $str = $str + 2014
  $str   #str = Хабрахабр2014
  

  
  
  
• If we need to find out what type this or that variable has, we can use the GetType () method
  
  

  $s = "Это строка?"
  $s.GetType().FullName
  

  
  
  
  
  
• The type of variable PowerShell determines automatically or can be assigned manually.
  
  

  $var = "one"
  [string]$var = "one"
  

  
  
  PowerShell uses the Microsoft .NET Framework data types. Consider the main ones:
  
  

  Type / .NET class	Description
  [string] System.String	Line $var = "one"
  [char] System.Char	Symbol $var = [char]0x263b
  [bool] System.Boolean	Boolean. It can be $ true or $ false . $bvar = $true
  [int] System.Int32	32-bit integer $i = 123456789
  [long] System.Int64	64-bit integer $long_var = 12345678910
  [decimal] System.Decimal	128 bit decimal number. The letter d at the end of the number is required $dec_var = 12345.6789d
  [double] System.Double	8-byte decimal floating-point number [double]$double_var = 12345.6789
  [single] System.Single	32 bit floating point number [single]$var = 123456789.101112
  [DateTime] System.DateTime	Variable date and time. $dt_var = Get-Date
  [array] System.Object []	Array The index of the elements of the array begins with 0 - to refer to the first element of the array $ mas, write $ mas [0] . $mas = "one", "two", "three"; To add an element to an array, you can write $mas = $mas + "four" Each element of the array can have its own type. $mas[4] = 1
  [hashtable] System.Collections.Hashtable	Hash tables. The difference between hash tables and arrays is that indexes are used in arrays and named keys are used in the hash table. Hash tables are built on the principle: @ {key = "value"} $ht = @{odin="one"; dva="two"; tri="three"} To add an item to the hash table, you can either assign it the key that does not exist yet, or use the Add () method . If assignment is done to an existing key, the key value will change to the assigned one. To remove an item from a hash table, there is a Remove () method . $ht.Add("chetyre", "four") $ht.pyat = "five" $ht.Remove("dva")

  
  

$MAC = Get-WmiObject -ComputerName domain-comp1, domain-comp2 -Class Win32_NetworkAdapterConfiguration -Filter IPEnabled=True  |  Select-Object -Property * | SELECT PSComputerName, @{Name="IPAddress";Expression={$_.IPAddress.get(0)}}, MACAddress, Description
$MAC

$MAC = Get-WmiObject -ComputerName . -Class Win32_NetworkAdapterConfiguration -Filter IPEnabled=True  |  Select-Object -Property * | SELECT PSComputerName, @{Name="IPAddress";Expression={$_.IPAddress.get(0)}}, MACAddress, Description
$MAC | Export-Csv D:comp_ip_mac.csv -Encoding UTF8

Variable Scope

$Global:var = 12

- Interesting, and if you set a function or variable in Russian in PowerShell, will it work?

- In theory, it should work, these are also symbols.

And yes, indeed:

function привет() { "Привет, $env:USERNAME. Может не стоит писать на русском?"
                    Start-Sleep 3
                    "Открыть Хабр?"
                    }
function открывай() { & "C:\Program Files\Internet Explorer\iexplore.exe" http://habrahabr.ru/post/242425/ }

Comparison operators and logical operators

• When the condition is met, the comparison construct always returns the boolean value $ true or $ false if the condition is false.

$var = "619"
$var -eq 123   #$false

$var = "619"
$var -ne 123   #$true

$var = "619"
$var -gt 123   #$true

$var = "619"
$var -ge 123   #$true

$var = "619"
$var -lt 123   #$false

$var = "619"
$var -le 123   #$false

"Habra" -like "habr*"   #true

"Habra" -notlike "habr*"   #false

1, 2, 3, 4, 5 -contains 3   #$true

1, 2, 3, 4, 5 -notcontains 3   #$false

$str = "http://habrahabr.ru"
$str -match "^http://(\S+)+(.ru)$"   #$true

$str = "http://habrahabr.ru"
$str -notmatch "^http://(\S+)+(.com)$"   #true

"Microhabr" -replace "Micro","Habra"   #Habrahabr

#Путь к профилю на удалённом компьютере
Function UProfile ($UCompName, $ULogin) {
        [string]$CompOS = Get-WmiObject -ComputerName $UCompName -Class Win32_OperatingSystem | SELECT Caption   #Получаем заголовок операционной системы компьютера
    if ($CompOS -match "Windows 7") {   #Если в заголовке содержится "Windows 7"
        [string]$LinkUserProfile = "\\$UCompName\d$\users\$ULogin"   #Получаем такой путь
        $LinkUserProfile  
    } elseif ($CompOS -match "Windows XP") {   #Если в заголовке содержится "Windows XP"
        [string]$LinkUserProfile = "\\$UCompName\d$\Documents and Settings\$ULogin"   #Получаем такой путь
        $LinkUserProfile        
    }
}
UProfile domain-comp1 Administrator   #функция имя-компьютера логин-пользователя

#Путь к профилю на удалённом компьютере
Function UProfile ($UCompName, $ULogin) {
        [string]$CompOS = Get-WmiObject -ComputerName $UCompName -Class Win32_OperatingSystem | SELECT Caption   #Получаем заголовок операционной системы компьютера
    if ($CompOS -match "Windows 7") {   #Если в заголовке содержится "Windows 7"
        [string]$LinkUserProfile = "\\$UCompName\d$\users\$ULogin"   #Получаем такой путь
    } elseif ($CompOS -match "Windows XP") {   #Если в заголовке содержится "Windows XP"
        [string]$LinkUserProfile = "\\$UCompName\d$\Documents and Settings\$ULogin"   #Получаем такой путь    
    }
    if (Test-Path $LinkUserProfile) { $LinkUserProfile } else { "Профиль $ULogin не существует на компьютере $UCompName" }   #Проверяем существование профиля
}
UProfile domain-comp1 Administrator   #функция имя-компьютера логин-пользователя

• You can optionally specify a condition if the comparison is case sensitive. To do this, substitute the letter " c " before the operator
  
  

  $str1 = "Habr"
  $str2 = "habr"
  $str1 -ceq $str2   #$false
  

  
  
  
• You can use multiple comparison operators using logical operators. Logical operators are listed in the table below:

("Строка" -eq "Строка") -and (619 -eq 619)   #$true

("Строка" -eq "Строка") -or (619 -eq 123)   #$true

-not (123 -gt 324)   #$true

!(123 -gt 324)   #$true

A few words about if ... elseif and else

if ( условие1-верно ) { выполняем-код }   #если условие 1 верно, выполняем код, если нет - идём дальше
elseif ( условие2-верно ) { выполняем-код }   #необязательное условие: иначе, если условие 2 верно, выполняем код
else { выполняем-код }  #необязательное условие: если прошлое условие не верно, выполняем код

$str = ""
if ( 1 -gt 2 ) { $str = "Апельсин" } 
elseif ( $str -eq "Апельсин" ) { $str } 
else { $str = "Яблоко"; $str } 

Answer

Information output

• Writing to a file using Out-File
  
  

  $str = "Hello Habr!"
  $str | Out-File D:\out_test1.txt
  

  
  or, as we said in Part I, use the " > " sign
  
  

  $str = "Hello Habr!"
  $str > D:\out_test2.txt
  

  
  
• Export data to .csv file using Export-Csv
  
  

  $p = Get-Process
  $p | SELECT Name, Path | Export-Csv -Path D:\out_test3.csv
  

  
  
• Writing to HTML file using ConvertTo-Html
  
  

  $h = Get-Process
  $h | ConvertTo-Html -Property Name, Path > D:\out_test4.html
  & D:\out_test4.html   #Откроем файле после формирования
  

  
  
  
  
  Working with HTML output is actually very nice. Having web programming skills, you can add styles and get very nice reports at the end.
  

Get-Content D:\out_test1.txt

Cycles

Do while

$x = 10
do
{
    $x
    $x = $x - 1    
}
while ($x -gt 0)

Do until

$x = 0
do
{
    $x
    $x = $x + 1    
}
until ($x -gt 10)

For

for ($i = 0; $i -lt 10; $i++)
{ 
    $i
}

Foreach

$collection = "Имя-Компьютера1", "Имя-Компьютера2", "Имя-Компьютера3"
foreach ($item in $collection)
{
    $item 
}

Writing functions

• Functions in PowerShell have the following structure:
  
  

  function имя-функции ([параметр1, ..., параметрN]) 
       { 
          тело-функции 
       } 
  

  
  
• Functions do not have to return a result.
• When calling a function, all parameters are separated by spaces.

function sqr ($a)
     {
      return $a * $a
     }
sqr 2   #Результат: 4

#Транслитерация
function Translit ([string]$inString)
{
    $Translit = @{    #Создаём хеш-таблицу соответствия символов
    [char]'а' = "a"
    [char]'А' = "A"
    [char]'б' = "b"
    [char]'Б' = "B"
    [char]'в' = "v"
    [char]'В' = "V"
    [char]'г' = "g"
    [char]'Г' = "G"
    [char]'д' = "d"
    [char]'Д' = "D"
    [char]'е' = "e"
    [char]'Е' = "E"
    [char]'ё' = "yo"
    [char]'Ё' = "Yo"
    [char]'ж' = "zh"
    [char]'Ж' = "Zh"
    [char]'з' = "z"
    [char]'З' = "Z"
    [char]'и' = "i"
    [char]'И' = "I"
    [char]'й' = "j"
    [char]'Й' = "J"
    [char]'к' = "k"
    [char]'К' = "K"
    [char]'л' = "l"
    [char]'Л' = "L"
    [char]'м' = "m"
    [char]'М' = "M"
    [char]'н' = "n"
    [char]'Н' = "N"
    [char]'о' = "o"
    [char]'О' = "O"
    [char]'п' = "p"
    [char]'П' = "P"
    [char]'р' = "r"
    [char]'Р' = "R"
    [char]'с' = "s"
    [char]'С' = "S"
    [char]'т' = "t"
    [char]'Т' = "T"
    [char]'у' = "u"
    [char]'У' = "U"
    [char]'ф' = "f"
    [char]'Ф' = "F"
    [char]'х' = "h"
    [char]'Х' = "H"
    [char]'ц' = "c"
    [char]'Ц' = "C"
    [char]'ч' = "ch"
    [char]'Ч' = "Ch"
    [char]'ш' = "sh"
    [char]'Ш' = "Sh"
    [char]'щ' = "sch"
    [char]'Щ' = "Sch"
    [char]'ъ' = ""
    [char]'Ъ' = ""
    [char]'ы' = "y"
    [char]'Ы' = "Y"
    [char]'ь' = ""
    [char]'Ь' = ""
    [char]'э' = "e"
    [char]'Э' = "E"
    [char]'ю' = "yu"
    [char]'Ю' = "Yu"
    [char]'я' = "ya"
    [char]'Я' = "Ya"
    }
    $TranslitText = ""
    foreach ($CHR in $inCHR = $inString.ToCharArray())
        {
        if ($Translit[$CHR] -cne $Null) 
            { $TranslitText += $Translit[$CHR] }   #аналог записи $TranslitText = $TranslitText + $Translit[$CHR] 
        else
            { $TranslitText += $CHR }
        }
    return $TranslitText
}
Translit Хабрахабр   #Вывод: Habrahabr

Afterword

To be continued...

Additional Information

• Jump Start in PowerShell (part I) ;
• Download PowerShell v.5 for free without registration ;
• Great MVA course: Advanced features and scripting in PowerShell 3.0 (Jump Start) . My advice is to look at the first 3 blocks, plunge into the language, try to perform some tasks, and after a week, watch the remaining blocks. Russian subtitles;
• TechDays theme video;
  PowerShell Script Gallery on Technet ;
  Blog PowerShell developers .