[Solved] You want to filter a list of filenames to include only those that start with... Which command correctly uses -match to do this?$files = @('log2020.txt', 'log2019.csv', 'data2020.log', 'log20a0.txt') | PowerShell

PowerShell - Operators

You want to filter a list of filenames to include only those that start with 'log' and end with a 4-digit year using PowerShell. Which command correctly uses -match to do this?

$files = @('log2020.txt', 'log2019.csv', 'data2020.log', 'log20a0.txt')

A$files | Where-Object { $_ -like 'log????' }

B$files | Where-Object { $_ -like 'log*2020' }

C$files | Where-Object { $_ -match 'log\d{4}$' }

D$files | Where-Object { $_ -match '^log\d{4}' }

Step-by-Step Solution

Solution:

Step 1: Understand the pattern requirements
We want filenames starting with 'log' (^log) followed immediately by exactly 4 digits (\d{4}).
Step 2: Analyze each option
$files | Where-Object { $_ -match '^log\d{4}' } uses regex '^log\d{4}' which matches strings starting with 'log' plus 4 digits. $files | Where-Object { $_ -like 'log????' } uses -like with 'log????' which matches 'log' plus any 4 characters but not necessarily digits. $files | Where-Object { $_ -match 'log\d{4}$' } matches 'log' followed by 4 digits at the end, but the year is not necessarily at the end of the filename. $files | Where-Object { $_ -like 'log*2020' } matches 'log' followed by anything and ending with '2020', which is too specific.
Final Answer:
$files | Where-Object { $_ -match '^log\d{4}' } -> Option D
Quick Check:
Start with 'log' + 4 digits = $files | Where-Object { $_ -match '^log\d{4}' } [OK]

Quick Trick: Use ^ for start and \d{4} for 4 digits in regex [OK]

Common Mistakes:

Using -like with ? instead of digits
Matching digits at end instead of start
Confusing -like and -match patterns

Master "Operators" in PowerShell

9 interactive learning modes - each teaches the same concept differently

Learn Why Deep Visual Try Challenge Project Recall Time

More PowerShell Quizzes

You want to filter a list of filenames to include only those that start with 'log' and end with a 4-digit year using PowerShell. Which command correctly uses -match to do this?

Step 1: Understand the pattern requirements

Step 2: Analyze each option

Final Answer:

Quick Check:

Want More Practice?