Return to site

Powershell Check If File Contains String

broken image


  • Long story short, I am putting together a quick script to check for DFS Replication backlogging. This all works beautifully until I encounter a Replication Group Name with a space in it. I am currently taking user input for a variable. If that input contains a space, I want to encapsulate the string in double quotes.
  • To check if the file exists, enter the command below in PowerShell and press enter. Test-Path -Path E: reports processes.txt. When I pressed, PowerShell returned True, meaning that the file exists. However, if I run the same command for a file that does not exists, PowerShell returns False. How to Combine Test-Path and IF Statement without a.

You can use the Where-Object cmdlet to filter objects from a collection based on their property values. We can use the comparison operator like with wildcard character to check if a property of object contains a specific string.

After the extraction of the file name and the value to check it will then import the CSV file which has that filename and check for the extracted value in it. If the CSV file contains the value it will append the values from the specified fields in the CSV file to the specified text file. Flexisign pro 10 with crack free download. How to check if a secure-string contains a number. I'm trying to figure out how to check if a file is open with PowerShell before continuing the rest of the script.

Note: You can not use the comparison operator contains to check the contains string, because it's designed to tell you if a collection of objects includes (‘contains') a particular object.

The following command returns all the processes in current machine.

If you want to list only the process which contains string '32' in processname, you need to use the below command.

By default like operator ignore the case-sensitive check. Civ vi mac torrent pirate bay. To perform a case-sensitive comparison just prefix the word 'c' with like operator ('clike').

If you want to check starts with string, you can use the same like operator with appending * at the end of the string alone.

File

Likewise, to check ends with string, need to append * at start of the string.

Related Reads

Introduction to The Windows PowerShell If Statement

PowerShell's ‘If' statement comes under the umbrella of flow control. Once you master the basic construction then you can increase its usefulness by appending, ‘Else' and ‘ElseIf' statements. One of my favourite alternative strategies is to use ‘Switch‘.

Topics for PowerShell's If Statement

Construction of the PowerShell ‘If' Statement

As with so many PowerShell constructions, the type of bracket signifies how to break the script into sections. It's worth tattooing into our memory that (parenthesis brackets are for the first part, namely the condition), while {braces are for the block command}.

Summary: In PowerShell, ‘If' executes statements conditional on the truth of the test expression.

Example 1a: Plain ‘If'

Learning Points

Note 1: Trace the above construction, and separate the two components: if (test) and {what to do}.

Text

Note 2: Avoid over-think; there is no ‘Then' in a PowerShell ‘If' statement. My advice is that instead of worrying about ‘If Then', pay close attention to the two types of bracket. Furthermore, there is no endif in PowerShell as there is in VBScript.

Note 3: To double check your understanding, try amending, 'Bigger than Zero' to a different text string, such as: 'Less than nought'. Once you have done that, set $Number to -1 in the above Example 1a.

Example 1b: PowerShell Script to Checks If a File Exists

Note 4: You probably want to change the file referenced by $ChkFile. Indeed, the script cries out to be modified for a more constructive {outcome}.

Note 5: You could easily append an else statement to cater for a file not existing.
Else {Write-Host 'File does not exist'}

Guy Recommends: Free WMI Monitor for PowerShell (FREE TOOL)

Windows Management Instrumentation (WMI) is one of the hidden treasures of Microsoft's operating systems. Fortunately, SolarWinds have created a Free WMI Monitor for PowerShell so that you can discover these gems of performance information, and thus improve your PowerShell scripts.

Take the guesswork out of which WMI counters to use when scripting the operating system, Active Directory, or Exchange Server. Give this WMI monitor a try – it's free.

If Logic and Tactics

It's rare that my first ‘If' construction produces the desired results. The secret of success is to experiment with the If test, or alternatively start introducing one or more ‘ElseIf tests with their corresponding {outcome block}.

In this example I have introduced -Not into the logic:

Example 1b: PowerShell If -Not Statement to Check for a Service

Note 6: This script uses the Display Name property of the service. Remember in PowerShell ‘If Then' does not exist. Observe it's plain ‘If'.

Powershell script to check if file contains string

Note 7: Observe in passing the If -Not construction; incidentally, -Not is sometimes abbreviated to an exclamation mark ! in PowerShell.

Note 8: This script cries out for an Else statement. We need to know if the named service has been installed.

Note 9: See more on -ErrorAction SilentlyContinue

Example 1c: PowerShell If Statement To Check IP Addresses

Here is another real-life example of the ‘If statement' in action. The idea is to ping 20 IP Addresses. The logic says If the StatusCode is 0, then display a label saying ‘ON NETWORK'.

Note 10: Once If statements get complicated it's time to investigate PowerShell's Switch parameter.

Guy Recommends: Network Performance Monitor (FREE TRIAL)

SolarWinds Network Performance Monitor (NPM) will help you discover what's happening on your network. This utility will also guide you through troubleshooting; the dashboard will indicate whether the root cause is a broken link, faulty equipment or resource overload.

What I like best is the way NPM suggests solutions to network problems. Its also has the ability to monitor the health of individual VMware virtual machines. If you are interested in troubleshooting, and creating network maps, then I recommend that you try NPM on a 30-day free trial.

Example 1d: File Content Example of Plain ‘If'

PowerShell has a batch of help files. One of these files contains help about the ‘if' statement. In the example below, $File references that file. $Content is set to the content of the file. The third line attempts to match a string to the contents of the file.

Learning Points

The above example is concerned with matching a string 'The if Statement' to the contents of the built in help file.

Example 2a: ‘If' With ‘Else'

Powershell Where String Contains

This example deal with plain ‘Else'. This is a simple command, unlike ElseIf there is no second test construction, ‘Else' just follows on to reflect what to do if the If statement is false.

Learning Points

The best way to see how ‘else' operates is to amend line 3 thus:
($File -Match 'The ifyyyy Statement').

Example 2b: Checking If a Service Has Been Installed

Guy Recommends: SolarWinds Engineer's Toolset (FREE TRIAL)

This Engineer's Toolset provides a comprehensive console of 50 utilities for troubleshooting computer problems. Guy says it helps me monitor what's occurring on the network, and each tool teaches me more about how the underlying system operates.

There are so many good gadgets; it's like having free rein of a sweetshop. Thankfully the utilities are displayed logically: monitoring, network discovery, diagnostic, and Cisco tools. Try the SolarWinds Engineer's Toolset on a 14-day free trial now!

Example 2c: PowerShell If -Not Logic

The purpose of this script is to employ -Not logic to check for the Alerter service. One scenario is you are working with Windows 7 machines, and they no longer install this service.

Observe how -Not reverses the ‘If' logic compared with Example 1.

Note 11: See more examples of PowerShell's If -Not logic.

Example 2d: NetSh

Word

Likewise, to check ends with string, need to append * at start of the string.

Related Reads

Introduction to The Windows PowerShell If Statement

PowerShell's ‘If' statement comes under the umbrella of flow control. Once you master the basic construction then you can increase its usefulness by appending, ‘Else' and ‘ElseIf' statements. One of my favourite alternative strategies is to use ‘Switch‘.

Topics for PowerShell's If Statement

Construction of the PowerShell ‘If' Statement

As with so many PowerShell constructions, the type of bracket signifies how to break the script into sections. It's worth tattooing into our memory that (parenthesis brackets are for the first part, namely the condition), while {braces are for the block command}.

Summary: In PowerShell, ‘If' executes statements conditional on the truth of the test expression.

Example 1a: Plain ‘If'

Learning Points

Note 1: Trace the above construction, and separate the two components: if (test) and {what to do}.

Note 2: Avoid over-think; there is no ‘Then' in a PowerShell ‘If' statement. My advice is that instead of worrying about ‘If Then', pay close attention to the two types of bracket. Furthermore, there is no endif in PowerShell as there is in VBScript.

Note 3: To double check your understanding, try amending, 'Bigger than Zero' to a different text string, such as: 'Less than nought'. Once you have done that, set $Number to -1 in the above Example 1a.

Example 1b: PowerShell Script to Checks If a File Exists

Note 4: You probably want to change the file referenced by $ChkFile. Indeed, the script cries out to be modified for a more constructive {outcome}.

Note 5: You could easily append an else statement to cater for a file not existing.
Else {Write-Host 'File does not exist'}

Guy Recommends: Free WMI Monitor for PowerShell (FREE TOOL)

Windows Management Instrumentation (WMI) is one of the hidden treasures of Microsoft's operating systems. Fortunately, SolarWinds have created a Free WMI Monitor for PowerShell so that you can discover these gems of performance information, and thus improve your PowerShell scripts.

Take the guesswork out of which WMI counters to use when scripting the operating system, Active Directory, or Exchange Server. Give this WMI monitor a try – it's free.

If Logic and Tactics

It's rare that my first ‘If' construction produces the desired results. The secret of success is to experiment with the If test, or alternatively start introducing one or more ‘ElseIf tests with their corresponding {outcome block}.

In this example I have introduced -Not into the logic:

Example 1b: PowerShell If -Not Statement to Check for a Service

Note 6: This script uses the Display Name property of the service. Remember in PowerShell ‘If Then' does not exist. Observe it's plain ‘If'.

Note 7: Observe in passing the If -Not construction; incidentally, -Not is sometimes abbreviated to an exclamation mark ! in PowerShell.

Note 8: This script cries out for an Else statement. We need to know if the named service has been installed.

Note 9: See more on -ErrorAction SilentlyContinue

Example 1c: PowerShell If Statement To Check IP Addresses

Here is another real-life example of the ‘If statement' in action. The idea is to ping 20 IP Addresses. The logic says If the StatusCode is 0, then display a label saying ‘ON NETWORK'.

Note 10: Once If statements get complicated it's time to investigate PowerShell's Switch parameter.

Guy Recommends: Network Performance Monitor (FREE TRIAL)

SolarWinds Network Performance Monitor (NPM) will help you discover what's happening on your network. This utility will also guide you through troubleshooting; the dashboard will indicate whether the root cause is a broken link, faulty equipment or resource overload.

What I like best is the way NPM suggests solutions to network problems. Its also has the ability to monitor the health of individual VMware virtual machines. If you are interested in troubleshooting, and creating network maps, then I recommend that you try NPM on a 30-day free trial.

Example 1d: File Content Example of Plain ‘If'

PowerShell has a batch of help files. One of these files contains help about the ‘if' statement. In the example below, $File references that file. $Content is set to the content of the file. The third line attempts to match a string to the contents of the file.

Learning Points

The above example is concerned with matching a string 'The if Statement' to the contents of the built in help file.

Example 2a: ‘If' With ‘Else'

Powershell Where String Contains

This example deal with plain ‘Else'. This is a simple command, unlike ElseIf there is no second test construction, ‘Else' just follows on to reflect what to do if the If statement is false.

Learning Points

The best way to see how ‘else' operates is to amend line 3 thus:
($File -Match 'The ifyyyy Statement').

Example 2b: Checking If a Service Has Been Installed

Guy Recommends: SolarWinds Engineer's Toolset (FREE TRIAL)

This Engineer's Toolset provides a comprehensive console of 50 utilities for troubleshooting computer problems. Guy says it helps me monitor what's occurring on the network, and each tool teaches me more about how the underlying system operates.

There are so many good gadgets; it's like having free rein of a sweetshop. Thankfully the utilities are displayed logically: monitoring, network discovery, diagnostic, and Cisco tools. Try the SolarWinds Engineer's Toolset on a 14-day free trial now!

Example 2c: PowerShell If -Not Logic

The purpose of this script is to employ -Not logic to check for the Alerter service. One scenario is you are working with Windows 7 machines, and they no longer install this service.

Observe how -Not reverses the ‘If' logic compared with Example 1.

Note 11: See more examples of PowerShell's If -Not logic.

Example 2d: NetSh

Powershell Check If File Contains String File

The purpose of this example is to check the status of a firewall on a Windows client machine such as Windows 8.1 or Windows 7.

Researching If, Else and ElseIf

  • For more information refer to the built-in About_If file
  • See how to disable Windows 8 firewalls with a Group Policy.

Example 3: ElseIf

This example has a real task; to check that we have the name of an actual file. Remember that the second (test statement) must be followed by a second {Block Script}.

Learning Points

Note 12: The advantage of ElseIf over plain Else, is that we can introduce a new test. In the above example we use ElseIf to check if the length of the file is less than 1. To activate the ‘ElseIf' block, set $File to a non-existent file for example
$File = Get-Help about_ifxx

AhnLab Asia Pacific Website - AhnLab. An industry-leading information security vendor, delivers a comprehensive security lineup including proven, world-class antivirus products, network security appliances, and advanced security services. Ahnlab. AhnLab V3 Home is the powerful solution that you've been looking for to protect your home IoT devices. Contact Us ※ Currently not for sale. We are preparing for the launch soon so please look forward to it. Industry-leading Home Security Solution.

Note 13: To trigger the final ‘Else', try changing:
$File = Get-Help about_if
to
$File = Get-Help about_scope

If you have time, you could add more ‘ElseIf' statements to cater for other eventualities. Alternatively, if the ElseIf construction is getting unwieldy, then try the superior switch command.

Guy Recommends: SolarWinds Admin Bundle for Active Directory (FREE TOOL)

Import users from a spreadsheet. Just provide a list of the users with their fields in the top row, and save as .csv file. Then launch this FREE utility and match your fields with AD's attributes, click and import the users.

Optionally, you can provide the name of the OU where the new accounts will be born. Download your FREE bulk import tool.

If you need more comprehensive application analysis software, Download a free trial of SAM (Server & Application Monitor)

About_If

If you would another account of PowerShell's If statement, then have a look at the built-in help file

This is Microsoft's explanation:

Windows PowerShell evaluates the conditional expression as either true or false. Should the result be true, PowerShell obeys whatever is inside the {curly brackets}, whereupon PowerShell exits the If statement.

In the event of the first test being false PowerShell works its way through the ElseIf statements.

Incidentally, the ‘Vehicle' for our tests reveals a whole family of ‘about_zyx…' files. My point is there is no command: ‘Get-Help if', however, there is a help file called, ‘about_if'. Furthermore, if you look in the PowerShell directory then you will see ‘About' files to assist with commands such as ‘If' and ‘ElseIf'. You can list these ‘About' files with the command:

Powershell Check If File Contains String Substring

Summary of PowerShell's If Construction

When it comes to filtering output, one of the oldest and best statements is the ‘If' clause. As usual, the secret of understanding the syntax is to pay close attention to the style of bracket. If (parenthesis for the test) and {braces for the action}. Once you have mastered the basic ‘If' statement, then extend your capabilities by researching ‘Else' and ‘ElseIf'.

If you like this page then please share it with your friends

See more Windows PowerShell flow control examples

• PowerShell Home • PowerShell If Statement • PowerShell ElseIf • Free Permissions Analyzer

• Conditional Operators • PowerShell -Match • PowerShell -Like • PowerShell -Contains

• PowerShell Comparison Operators • PowerShell Syntax • Where Filter • PowerShell Else

Powershell Check If File Contains String Recursive

Please email me if you have a better example script. Also please report any factual mistakes, grammatical errors or broken links, I will be happy to correct the fault.





broken image