![\"Image](\"https:\/\/devblogs.microsoft.com\/wp-content\/uploads\/sites\/29\/2019\/02\/bestpracticebookcover.jpg\" "\\"Image")
<\/a><\/p>\nWhen you are searching for a string, you can use at least three operators: −contains<\/b>, −like<\/b>, or −match<\/b>.<\/p>\nThe −contains operator<\/h2>\n
The most confusing of the bunch is the −contains<\/b> operator. This is not due to its complexity of use, but rather, to an attempt at understanding when to use the operator. Perhaps a few examples will help.<\/p>\n
In the following script, an array of numbers is created and stored in the $a<\/b> variable. Next, the −contains<\/b> operator is used to see whether the array that is stored in the $a<\/b> variable contains the number 1. It does, and True<\/b> is reported. The −contains<\/b> operator is then used to see whether the $a<\/b> array contains the number 6. It does not, and False<\/b> is reported.<\/p>\n
PS C:\\> $a = 1,2,3,4,5
PS C:\\> $a -contains 1
True
PS C:\\> $a -contains 6
False<\/p>\n
In the next example, the number 12345 is stored in the $b<\/b> variable. The −contains<\/b> method is used to see whether the number that is stored in $b<\/b> contains the number 4. Although the number 4 is indeed present in the number 12345, −contains<\/b> reports False<\/b>. The number stored in $b<\/b> does not contain 4. Next, the −contains<\/b> method is used to see whether $b<\/b> contains 12345, which it does, and True<\/b> is reported.<\/p>\n
PS C:\\> $b = 12345
PS C:\\> $b -contains 4
False
PS C:\\> $b -contains 12345
True<\/p>\n
Suppose that the variable $c<\/b> stores the following string:<\/p>\n
“This is a string.”<\/p>\n
When the −contains<\/b> method is used to look for the string “is”<\/b>, False<\/b> is returned. If the −contains<\/b> method is used to look for the string “This is a string”<\/b>, it returns True<\/b> as shown here.<\/p>\n
PS C:\\> $c = "This is a string"
PS C:\\> $c -contains "is"
False
PS C:\\> $c -contains "This is a string"
True<\/p>\n
For our last example of the −contains<\/b> operator, if $d<\/b> contains an array of strings ("This","is","a","string"<\/b>) when the −contains<\/b> operator is used to look for the value of “is”<\/b>, True<\/b> is returned. When the −contains<\/b> operator looks for “ring”<\/b>, it returns False<\/b>.<\/p>\n
PS C:\\> $d = "This","is","a","string"
PS C:\\> $d -contains "is"
True
PS C:\\> $d -contains "ring"
False<\/p>\n
The −contains<\/b> operator is used to examine the elements of an array. If the array contains a particular value, the operator returns True<\/b>. If there is not an exact match for the value, the −contains<\/b> operator returns False<\/b>. This process can be an easy way to locate items in an array.<\/p>\nThe −like operator<\/h2>\n
The −like<\/b> operator is used to perform a wildcard search in a string. If the $a<\/b> variable is used to hold the string “This is a string”, and the −like<\/b> operator searches for “*ring*”<\/b> , the −like<\/b> operator returns True<\/b> as shown here.<\/p>\n
PS C:\\> $a = "This is a string"
PS C:\\> $a -like "*ring*"
True<\/p>\n
An interesting use of the −like<\/b> operator is to search the elements of an array. If the $b<\/b> variable is used to hold the array “This”,”is”,”a”,”string”<\/b> , and the −like<\/b> operator searches the array for “*ring*”<\/b>, every match for the wildcard pattern is returned—not just a True or False answer.<\/p>\n
PS C:\\> $b = "This","is","a","string"
PS C:\\> $b -like "*ring*"
string<\/p>\n
The −match operator<\/h2>\n
The −match<\/b> operator is used to perform a regular expression pattern match. When the match is found, True<\/b> is returned. If a match is not found, False<\/b> is returned. If the $a<\/b> variable is assigned the value "This is a string"<\/b>, and the −match<\/b> operator is used to look for the value of “is”<\/b>, the pattern is a match, and True<\/b> is returned as shown here.<\/p>\n
PS C:\\> $a = "This is a string"
PS C:\\> $a -match "is"
True<\/p>\n
More complex match patterns can be used. For example, the \\w<\/b> character is used with regular expressions to look for any white space, such as a space before or after a letter. When the $a<\/b> variable is used to hold the string "This is a string"<\/b> and the regular expression pattern [\\w a \\w]<\/b> is used, a match will be returned if the letter a<\/b> is found with a space in front and a space behind the letter, as shown here.<\/p>\n
PS C:\\> $a = "This is a string"
PS C:\\> $a -match "[\\w a \\w]"
True<\/p>\n
What about matching with an array? If the $c<\/b> variable is used to hold the array "This","is","a","string"<\/b> and the regular expression pattern match “is”<\/b> is used, two matches are found. In this example, the actual string that contains the pattern match is returned. When a match is found, an array of strings is returned.<\/p>\n
PS C:\\> $c = "This","is","a","string"
PS C:\\> $c -match "is"
This
is<\/p>\n
Join me tomorrow when I will talk about more cool Windows PowerShell stuff.<\/p>\n
I invite you to follow me on Twitter<\/a> and Facebook<\/a>. If you have any questions, send email to me at scripter@microsoft.com<\/a>, or post your questions on the Official Scripting Guys Forum<\/a>. See you tomorrow. Until then, peace.<\/p>\nEd Wilson, Microsoft Scripting Guy<\/b> <\/p>\n","protected":false},"excerpt":{"rendered":"
Summary: Microsoft Scripting Guy, Ed Wilson, provides an excerpt from his new book, Windows PowerShell Best Practices, about searching for strings. Microsoft Scripting Guy, Ed Wilson, is here. Today I have an excerpt from my new book, PowerShell Best Practices , which is published by Microsoft Press. When you are searching for a string, you […]<\/p>\n","protected":false},"author":596,"featured_media":87096,"comment_status":"open","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"_acf_changed":false,"footnotes":""},"categories":[1],"tags":[331,460,3,4,45],"class_list":["post-2171","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-scripting","tag-best-practices","tag-powershell-4","tag-scripting-guy","tag-scripting-techniques","tag-windows-powershell"],"acf":[],"blog_post_summary":"
Summary: Microsoft Scripting Guy, Ed Wilson, provides an excerpt from his new book, Windows PowerShell Best Practices, about searching for strings. Microsoft Scripting Guy, Ed Wilson, is here. Today I have an excerpt from my new book, PowerShell Best Practices , which is published by Microsoft Press. When you are searching for a string, you […]<\/p>\n","_links":{"self":[{"href":"https:\/\/devblogs.microsoft.com\/scripting\/wp-json\/wp\/v2\/posts\/2171","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/devblogs.microsoft.com\/scripting\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/devblogs.microsoft.com\/scripting\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/devblogs.microsoft.com\/scripting\/wp-json\/wp\/v2\/users\/596"}],"replies":[{"embeddable":true,"href":"https:\/\/devblogs.microsoft.com\/scripting\/wp-json\/wp\/v2\/comments?post=2171"}],"version-history":[{"count":0,"href":"https:\/\/devblogs.microsoft.com\/scripting\/wp-json\/wp\/v2\/posts\/2171\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/devblogs.microsoft.com\/scripting\/wp-json\/wp\/v2\/media\/87096"}],"wp:attachment":[{"href":"https:\/\/devblogs.microsoft.com\/scripting\/wp-json\/wp\/v2\/media?parent=2171"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/devblogs.microsoft.com\/scripting\/wp-json\/wp\/v2\/categories?post=2171"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/devblogs.microsoft.com\/scripting\/wp-json\/wp\/v2\/tags?post=2171"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}