Loop through multiple array in powershell - powershell

I have 2 arrays here one contains the servername and other contains the IP.
I need to loop through them and create a key value pair like below for each server
server1:ip1
server2:ip2
I have written below code, but the problem is if i debug the code using F11, it is working fine, but i don't it gives some error which is different every time.
so feeling like it is not that reliable piece to continue.
$NewDNSEntryName = $DNSEntryName.Split(",")
$DNSIPs = $DNSIP.Split(",")
if($DNSEntryName -match "," -or $DNSIP -match ",")
{
0..($NewDNSEntryName.Count - 1) | ForEach-Object {
$fullName=""
$fullName += #("$($NewDNSEntryName[$_]):$($DNSIPs[$_])")
This is the line where i am facing trouble
0..($NewDNSEntryName.Count - 1) | ForEach-Object
Please let me know why this code is behaving like this else any alternate idea is appreciated

Assuming each item in each list corresponds with each other exactly, you can use a for loop and loop through the array indexes.
$NewDNSEntryName = $DNSEntryName.Split(",")
$DNSIPs = $DNSIP.Split(",")
for ($i = 0; $i -lt $DNSIPs.count; $i++) {
"{0}:{1}" -f $NewDNSEntryName[$i],$DNSIPs[$i]
}
For the code above to work, $DNSEntryName and $DNSIP must be single strings with commas between names and IPs. If $DNSEntryName and $DNSIP are already lists or arrays, something else will need to be done.
In your attempt, technically, your logic should work given everything written above is true. However, $fullName is emptied at every single iteration, which may produce undesirable results.

Related

Running a for loop in Powershell

I am new o scripting in powershell and am from a Python background. I want to know if I'm doing this right.
I created this array and want to extract each item one by one
$M365_E3_Grps = ("O365-CHN-DomainUser,O365-Vendor-Exchange-User")
ForEach ($Indiv_Grp in $M365_E3_Grps) {
ForEach ($Indiv_Grp in $M365_E3_Grps) {
`$ADGroup = $Indiv_Grp$ADGroup = $Indiv_Grp`
I want to know if we can extract vals with a for loop like this and assign it to a variable like this.
Construct of your array
Your array is not quite correct and will be populated as a string. To create a string array you will need to quote each item in comma separated list. The parentheses are also not required.
$M365_E3_Grps = "O365-CHN-DomainUser","O365-Vendor-Exchange-User"
Your foreach keyword syntax is however correct, even if the formatting in your question was slightly off.
foreach ($Indiv_Grp in $M365_E3_Grps) {
# Assigning $Indiv_Grp to $ADGroup here is kind of redundant since
# the value is already assinged to $Indiv_Grp
$Indiv_Grp
}

Getting error when adding nested hashtable to array in Powershell

I have a nested hashtable with an array and I want to loop through the contents of another array and add that to the nested hashtable. I'm trying to build a Slack message block.
Here's the nested hashtable I want to add to:
$msgdata = #{
blocks = #(
#{
type = 'section'
text = #{
type = 'mrkdwn'
text = '*Services Being Used This Month*'
}
}
#{
type = 'divider'
}
)
}
$rows = [ ['azure vm', 'centralus'], ['azure sql', 'eastus'], ['azure functions', 'centralus'], ['azure monitor', 'eastus2'] ]
$serviceitems = #()
foreach ($r in $rows) {
$servicetext = "*{0}* - {1}" -f $r[1], $r[0]
$serviceitems += #{'type'='section'}
$serviceitems += #{'text'= ''}
$serviceitems.text.Add('type'='mrkdwn')
$serviceitems.text.Add('text'=$servicetext)
$serviceitems += #{'type'='divider'}
}
$msgdata.blocks += $serviceitems
The code is partially working. The hashtables #{'type'='section'} and #{'type'='divider'} get added successfully. Trying to add the nested hashtable of #{'text' = #{ 'type'='mrkdwn' 'text'=$servicetext }} fails with this error:
Line |
24 | $serviceitems.text.Add('type'='mrkdwn')
| ~
| Missing ')' in method call.
I tried looking through various Powershell posts and couldn't find one that applies to my specific situation. I'm brand new to using hashtables in Powershell.
Complementing mklement0's helpful answer, which solves the problem with your existing code, I suggest the following refactoring, using inline hashtables:
$serviceitems = foreach ($r in $rows) {
#{
type = 'section'
text = #{
type = 'mrkdwn'
text = "*{0}* - {1}" -f $r[1], $r[0]
}
}
#{
type = 'divider'
}
}
$msgdata.blocks += $serviceitems
This looks much cleaner and thus easier to maintain in my opinion.
Explanations:
$serviceitems = foreach ... captures all output (to the success stream) of the foreach loop in variable $serviceitems. PowerShell automatically creates an array from the output, which is more efficient than manually adding to an array using the += operator. Using += PowerShell has to recreate an array of the new size for each addition, because arrays are actually of fixed size. When PowerShell automatically creates an array, it uses a more efficient data structure internally.
By writing out an inline hash table, without assigning it to a variable, PowerShell implicitly outputs the data, in effect adding it to the $serviceitems array.
We output two hash tables per loop iteration, so PowerShells adds two array elements to $serviceitems per loop iteration.
Note:
This answer addresses your question as asked, specifically its syntax problems.
For a superior solution that bypasses the original problems in favor of streamlined code, see zett42's helpful answer.
$serviceitems.text.Add('type'='mrkdwn') causes a syntax error.
Generally speaking, IF $serviceitems.text referred to a hashtable (dictionary), you need either:
method syntax with distinct, ,-separated arguments:
$serviceitems.text.Add('type', 'mrkdwn')
or index syntax (which would quietly overwrite an existing entry, if present):
$serviceitems.text['type'] = 'mrkdwn'
PowerShell even lets you access hashtable (dictionary) entries with member-access syntax (dot notation):
$serviceitems.text.type = 'mrkdwn'
In your specific case, additional considerations come into play:
You're accessing a hashtable via an array, instead of directly.
The text entry you're trying to target isn't originally a nested hashtable, so you cannot call .Add() on it; instead, you must assign a new hashtable to it.
Therefore:
# Define an empty array
$serviceItems = #()
# "Extend" the array by adding a hashtable.
# Note: Except with small arrays, growing them with +=
# should be avoided, because a *new* array must be allocated
# every time.
$serviceItems += #{ text = '' }
# Refer to the hashtable via the array's last element (-1),
# and assign a nested hashtable to it.
$serviceItems[-1].text = #{ 'type' = 'mrkdwn' }
# Output the result.
$serviceItems

PowerShell array/index/variable

The below code is checking in a dropdownbox, which item has been selected and then is searched in several arrays and as soon found, the loop is broken through break and I receive the correct information in "`$$($array.name)".
$search = $CreateNewUserFormDropDownBoxLocation.SelectedItem.Split('-')[$($CreateNewUserFormDropDownBoxLocation.SelectedItem.Split('-').Count - 1)].Trim() + '*'
$AllLocations = (Get-Variable -Include USPennsylvaniaAve, USSixthStreet, USRodeoDrive, USOneMicrosoftWay,`
USNorthTantauAvenue, USMarketStreet, USMainStreet, USEmilyDrive,`
USCalle8, USBroadway, US18thStreetNW, UKOxfordStreet, UKDowningStreet,`
UKBondStreet, FRRuedeRivoli, FRChampsElysees, CHBahnhofstrasse,`
CA17thAvenue) | ? {$_.value -is [array]}
foreach ($Array in $AllLocations) {
if ($array.value -like $search) {
break
}
}
$test = "`$$($array.name)"
The issue is the variable $test does contain the correct array and I am interested, to work with the index (I hope I say that correctly).
For example, after the code ran and I enter $test, the result is for example $USMarketStreet, which is one of my arrays.
If I try to get the first index by typing $test[0] I do not get the expected content from the array, it gives me $.
If I enter $test[0..4] I get:
$
U
S
M
a
My intention was, to get the first key out of the array but instead of that, I am getting the first character out of the array name.
Is there a trick, how I can get to it? I also tried to play around with $array and $array.value but no success.

Invoke-RestMethod and foreach loop

Via PowerShell I'm trying to get the last ticker data from all currency pairs via the public API of a cryptocurrency exchange.
For this I first get all markets and then I want to loop through these, but for some reason only the first currency pair is being returned.
Anyone knows what I'm missing?
$bt_baseapi_url = "https://bittrex.com/api/v1.1/"
$getmarkets = $bt_baseapi_url + "public/getmarkets"
$getticker = $bt_baseapi_url + "public/getticker"
$markets = Invoke-RestMethod -Uri $getmarkets
$marketnames = $markets.result
foreach ($marketname in $marketnames.marketname) {
$tickerurl = $getticker + "?market=" + $marketname
$ticker = Invoke-RestMethod -Uri $tickerurl
return $ticker.result.last
}
As Ansgar Wiechers suggests in a comment on the question, do not use return inside a foreach statement's body in an attempt to return (output) a value while continuing the loop; return would return from any enclosing function or script.
Instead, rely on PowerShell's implicit output behavior, as demonstrated in this simple example:
> foreach ($el in 1, 2, 3) { $el }
1
2
3
Simply referencing $el without assigning to a variable or piping / redirecting it elsewhere cause its value to be output.
If needed at all, use continue to prevent execution of subsequent statements in the loop body while continuing the loop overall; use break to exit the loop.
By contrast - and that may be the source of the confusion - inside the body of a ForEach-Object cmdlet call - as part of a pipeline - rather than the foreach statement, the rules change, and return indeed would only exit the iteration at hand and proceed with the next input object:
> 1, 2, 3 | ForEach-Object { return $_ }
1
2
3
Note that even in this case return $_ is just syntactic sugar for $_; return - i.e., an output generating statement followed by a control-flow statement, and simply using $_ may be enough.
Do NOT use break / continue with the ForEach-Object cmdlet, as these statements would look for an enclosing loop statement (such as foreach, do, while`) and - in the absence of one - exit the entire script.
Unfortunately, there is no direct way to exit a pipeline prematurely, - see https://github.com/PowerShell/PowerShell/issues/3821; make your voice heard there if you think this should change.

Returning a Row Count for a DataRow in PowerShell

My script is populating a datarow from a stored procedure in SQL Server. I then reference specific columns in this datarow throughout the script. What I'm trying to do is add functionality that takes action X if the row count = 0, action Y if the row count = 1, and action Z if the row count > 1.
-- PowerShell script snippet
# $MyResult is populated earlier;
# GetType() returns Name=DataRow, BaseType=System.Object
# this works
ForEach ($MyRow In $MyResult) {
$MyFile = Get-Content $MyRow.FileName
# do other cool stuff
}
# this is what I'm trying to do, but doesn't work
If ($MyResult.Count -eq 0) {
# do something
}
ElseIf ($MyResult.Count -eq 1) {
# do something else
}
Else {
# do this instead
}
I can get $MyResult.Count to work if I'm using an array, but then I can't reference $MyRow.FileName directly.
This is probably pretty simple, but I'm new to PowerShell and object-oriented languages. I've tried searching this site, The Scripting Guy's blog, and Google, but I haven't been able to find anything that shows me how to do this.
Any help is much appreciated.
It has everything to do with how you populate $MyResult. If you query the database like
$MyResult = #( << code that returns results from database >> )
that is, enclosing the code that returns your dataset/datatable from the database within #( ... ), then number of rows returned will be easily checked using $MyResult.count.
Your original code should work as-is if you populate $MyResult this way.
I know this thread is old, but if someone else finds it on Google, this should work also on PS V5:
Replace $MyResult.Count with: ($MyResult | Measure-Object | select -ExpandProperty Count)
For Example:
If (($MyResult | Measure-Object | select -ExpandProperty Count) -eq 0)
I don't have experience with PS and SQL, but I'll try to provide an answer for you. If you're object $myresult is a datarow-object, it means you only got the one row. If the results are empty, then $myresult will usually be null.
If you get one or more rows, you can put them in an array and count it. However, if your $myresult are null, and you put it in an array it will still count as one, so we need to watch out for that. Try this:
If ($MyResult -eq $null) {
# do something if no rows
}
Else If (#($MyResult).Count -eq 1) {
# do something else if there are 1 rows.
# The cast to array was only in the if-test,
# so you can reach the object with $myresult.
}
Else {
# do this if there are multiple rows.
}
Looks like this question gets a lot of views, so I wanted to post how I handled this. :)
Basically, the fix for me was to change the method I was using to execute a query on SQL Server. I switched to Chad Miller's Invoke-SqlCmd2 script: TechNet: Invoke-SqlCmd2, i.e.
# ---------------
# this code works
# ---------------
# Register the function
. .\Invoke-Sqlcmd2.ps1
# make SQL Server call & store results to an array, $MyResults
[array]$MyResults = Invoke-Sqlcmd2 -Serve
rInstance "(local)" -Query "SELECT TOP 1 * FROM sys.databases;"
If ($MyResult -eq $null) {
# do something
}
ElseIf ($MyResult.Count -eq 1) {
# do something else
}
Else {
# do this instead
}