Converting bytes to megabytes on the fly - powershell

Question

In the PS command below I'm getting the name, creationTimeStamp, Disk_Size and storageBytes of yesterday's snapshots in my gcp project and outputting the data to a csv file (which is later converted to HTML and emailed):
$csv = gcloud --project $gcpProject compute snapshots list --format="csv(name,creationTimestamp,diskSizeGb,storageBytes)" --filter="creationTimestamp.date('%Y-%m-%d')=$yesterday" | Out-File C:\data.csv
The result looks something like this (the number of snapshots displayed varies):
+---------------------------+-------------------------------+--------------+---------------+
| NAME | CREATION_TIMESTAMP | DISK_SIZE_GB | STORAGE_BYTES |
+---------------------------+-------------------------------+--------------+---------------+
| snapshot1-us-central1 | 2019-10-24T19:24:09.061-07:00 | 50 | 1250586048 |
| snapshot2-data-us-east1 | 2019-10-24T19:01:49.791-07:00 | 150 | 425018600 |
+---------------------------+-------------------------------+--------------+---------------+
This is good except that the STORAGE_BYTES data is all in bytes thus making it hard to read. How can I record this data in MB instead in the csv file (or just replacing this data in the csv file that's in bytes with MB)

Answer 1

$data=Get-Content C:\data.csv
$NewData=#($data[0..2])#Adding Header in a new Variable
$Data[3..$($data.Count - 2)]|Foreach{
$startRange=$_.LastIndexOf("| ")+1
$length=$_.LastIndexOf(" |") - $_.LastIndexOf("| ")
#Converting Bytes into MB and replacing in the line
$NewData+=$_.Replace(($_.Substring($startRange,$length)).Trim(),"$([math]::Round(($_.Substring($startRange,$length)/1MB),2)) ")
}
#Adding last line
$NewData+=$data[$data.Count - 1]
#Modifying exsiting file
$NewData |Set-Content C:\data.csv -Force

Answer 2

I think, it should be simple using GCP PowerShell cmdlets.
Get-GceSnapshot -Project $gcpProject
I never used it, but you can use calculated properties to convert the size in oneline, an example below
Get-Process | Select-Object -First 3 -Property Name,#{E={$_.STORAGE_BYTES/1024};L='Size'}
PS: assuming the size property name is STORAGE_BYTES
https://googlecloudplatform.github.io/google-cloud-powershell/#/google-compute-engine/GceSnapshot/Get-GceSnapshot