Reading Multiple Entry from CSV using PowerShell - powershell

Question

I have a CSV file that contains multiple vendors (Cisco, Redhat, vmware..etc), I need a PowerShell script to read this column (vendor) and add separate column "Multiple1 or Multiple2" (Remark) if the CSV contains multiple entries of same vendors.
I have attached screen shot of the sample file.
I tried from end to get this done, but it didn't work.

Answer 1

Okay, after Spikeys last comment I had a go at guessing what he might want to achieve.
I created a CSV file:
Product,Template
Microsoft Windows,
RedHat Enterprise,
Apple Safari,
Microsoft Windows,
RedHat Enterprise,
RedHat Enterprise,
and then wrote the following script. It's commented and produces the following output:
Product Template
------- --------
Microsoft Windows Multiple2
RedHat Enterprise Multiple3
Apple Safari Multiple1
Microsoft Windows Multiple2
RedHat Enterprise Multiple3
RedHat Enterprise Multiple3
Code:
$Csv = Import-Csv -Path "C:\Book1.csv"
#Hastables have key - value pairs. Example "Microsoft Windows" = 1. Here 'Microsoft Windows' is the key and '1' is the value
[hashtable]$ProductCount = #{}
#Go through each line in the CSV. This returns the product name e.g. Microsoft Windows
ForEach ($Product in $Csv.Product)
{
#If there us no key for the current product in hashtable $Productcount, then add it with value 1
If ($ProductCount.Keys -notcontains $Product)
{
$ProductCount.Add($Product, 1)
}
#If the above does not apply, then increase the value (effectively the count) by 1
Else
{
$ProductCount[$Product] = $ProductCount[$Product] + 1
}
}
#Go through each row in the CSV file. Each row is returned as it's own object with a 'Product' and 'Template' property
ForEach ($Row in $Csv)
{
#Extract the count for the current product from hastable $ProductCount
$Count = $ProductCount[$Row.Product]
#Set the 'Template' property for the current row object to multipile + the count we got earlier
$Row.Template = "Multiple$Count"
}
#Save the changes to the CSV file as a new CSV. You can also overwrite your old one if you like
$Csv | Export-Csv -Path "C:\Book2.csv"
I don't quite understand your question, but here are some techniques I find useful when working with CSV files.
Example CSV:
Name,City
Bob,BlackPool
Alice,Dover
Carl,Manchester
Presume you assign the CSV file to a variable like so
$CSV = Import-CSV -Path "C:\Stuff.csv"
1. You can access all rows in a column by typing the variable dot(.) column header, so
$CSV.Name
returns:
Bob
Alice
Carl
2. To access a row in a CSV file you need to use indexing, so
$CSV[1]
returns:
Name City
---- ----
Alice Dover
3. An easy way to replace a property of a specific row is to filter it using Where-Object. Say I want to change Carl's city to London.
$($CSV | Where-Object {$_.Name -like "Carl"}).City = "London"
Here is what happens:
What's in the parentheses is processed first, so we are selecting a row where the Name property is like "Carl" (You can use wilcard here, so "Ca*" would have worked too). Then, outside of the parentheses, we are setting the city property to "London".
Note: $_ represents the data currently in a pipeline, in this case that's the row containing Carl.
There is more stuff to know, but this might help you the most.
Don't forget to save your changes by using the Export-CSV cmdlet!
$CSV | Export-CSV -Path "C:\new.csv" -NoTypeInformation