XYZ Dispatcher Agent 'XYZ' is starting task '12821_1' at Tue Nov 12 01:01:49 2019.
Above is the first line in a log file I want to pull out the "Tue Nov 12 01:01:49 2019" in a variable using Powershell. I have tried using REGEX but facing issues with it. A logfile will always start with this kind of line so I need to pull out the date and time to know the start time of the task using this log.
If your files consistently have the format described in your post, you can do the following:
$regex = '\w{3} \w{3} \d{2} \d{2}:\d{2}:\d{2} \d{4}'
$firstline = Get-Content '\\somepath\AgentLog_12821_1_12821_1.dsp.log' -TotalCount 1 |
Where-Object {$_ -match $regex}
$dateTimeString = $Matches[0]
The $Matches automatic variable is a hash table of values based on the previous successful -match result. It requires a successful match in order to automatically update the variable. You can $null the value.
If you want to capture all date matches in a file (one per line), you can use the following. This will capture all dates in an indexed collection ($dateTimeString).
$regex = '\w{3} \w{3} \d{2} \d{2}:\d{2}:\d{2} \d{4}'
$dateTimeString = (Select-String -Path '\\somepath\AgentLog_12821_1_12821_1.dsp.log' -Pattern $regex).Matches.Value
$dateTimeString[0] # First date