Php if string begins with string

Check if a String Starts With a Specified String in PHP

PHP String Functions In this chapter we will look at some commonly used functions to manipulate strings. The length of the strings to be compared is three.

PHP Strings

A string is a sequence of characters, like «Hello world!».

PHP String Functions

In this chapter we will look at some commonly used functions to manipulate strings.

strlen() — Return the Length of a String

The PHP strlen() function returns the length of a string.

Example

Return the length of the string «Hello world!»:

str_word_count() — Count Words in a String

The PHP str_word_count() function counts the number of words in a string.

Example

Count the number of word in the string «Hello world!»:

strrev() — Reverse a String

Example

Reverse the string «Hello world!»:

strpos() — Search For a Text Within a String

The PHP strpos() function searches for a specific text within a string. If a match is found, the function returns the character position of the first match. If no match is found, it will return FALSE.

Example

Search for the text «world» in the string «Hello world!»:

Tip: The first character position in a string is 0 (not 1).

str_replace() — Replace Text Within a String

The PHP str_replace() function replaces some characters with some other characters in a string.

Example

Replace the text «world» with «Dolly»:

Complete PHP String Reference

For a complete reference of all String Functions , go to our complete PHP String Reference.

The PHP string reference contains description and example of use, for each function!

PHP Exercises

Php check if string starts with string Code Example, All Languages >> PHP >> WordPress >> php check if string starts with string “php check if string starts with string” Code Answer’s. php string starts with . php by Vic20 on Sep 01 2020 Comment

Php if string begins with 1

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phpCopyelse echo "The string does not start with the desired substring."; ?>

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Check if a String Starts With a Specified String in PHP

In this article, we will introduce methods to check if a string starts with a specified string in PHP.

Use substr() Function to Check if a String Starts With a Specified String in PHP

The built-in function substr() is used to access a substring. The string is passed as an input, and the substring that we want to access is returned. We can use this function to check if a string starts with a specific string. The correct syntax to use this function is as follows

substr($string, $startPosition, $lengthOfSubstring); 

This function has three parameters. The details of its parameters are as follows.

Parameters	Description
$string	mandatory	The original string whose substring we wish to access.
$startPosition	mandatory	An integer variable. It tells the position where our substring will start. If it is positive, then our sub string starts from the left side of the string i.e from the beginning. If it is negative, then our substring starts from the end.
$lengthOfSubstring	optional	An integer variable. It specifies the total length of the string from the start position. If it is omitted, then the substring from the start position to the end of the string is returned. If it is negative, then the string from the end is removed according to its value. If it is zero, then an empty string is returned.

else echo "The string does not start with the desired substring."; ?> 

In the above code, we want to check if our string starts with Mr. .

0 is the start index of the substring, or in other words, the substring starts from the first character of the given string.

3 means the length of the returned substring is 3.

If the start of the string is the same as Mr. then it will display The string starts with the desired substring. .

The string starts with the desired substring. 

Use strpos() Function to check if a String Starts With a Specified String in PHP

The function strpos() returns the position of the first occurrence of a substring in the given string . We could use it to check if a string starts with a specified string.

If the returned value is 0 , it means the given string starts with the specified substring. Otherwise, the string doesn’t start with the checked substring .

strpos() is a case sensitive function. The correct syntax to use this function is as follows.

strpos($string, $searchString, $startPosition); 

It has three parameters. The details of its parameters are as follows.

Parameter	Description
$string	mandatory	It is the string whose substring we wish to find.
$searchString	mandatory	It is the substring that will be searched in a string.
$startPosition	optional	It is the position in the string from where the search will start.

else echo "The string does not start with the desired substring."; ?> 

Here, we have checked if our string starts with Mr. by finding the first occurrence of Mr. .

The string starts with the desired substring. 

Use strncmp() Function to Check if a String Starts With a Specified String in PHP

The built-in function strncmp() compares two given strings . This function is also case sensitive. The correct syntax to use this function is as follows.

strncmp($string1, $string2, $length); 

It has three parameters. The details of its parameters are as follows.

Parameters	Description
$string1	mandatory	It is the first string to be compared.
$string2	mandatory	It is the second string to be compared.
$length	mandatory	It is the length of the string to be compared.

It returns zero if both the strings are equal. This is a case sensitive function.

else echo "The string does not start with the desired substring."; ?> 

Here, the two strings are compared. The length of the strings to be compared is three.

The string starts with the desired substring. 

The case insensitive version of strncmp is strncasecmp . It compares the first n characters of the given two strings regardless of their cases.

else echo "The string does not start with the desired substring."; ?> 

The string starts with the desired substring. 

PHP String

Php starts with Code Example, //php check if first four characters of a string = http substr( $http, 0, 4 ) === «http»; //php check if first five characters of a string = https substr( $https, 0

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str_starts_with

Performs a case-sensitive check indicating if haystack begins with needle .

Parameters

The substring to search for in the haystack .

Return Values

Returns true if haystack begins with needle , false otherwise.

Examples

Example #1 Using the empty string »

The above example will output:

All strings start with the empty string

Example #2 Showing case-sensitivity

$string = ‘The lazy fox jumped over the fence’ ;

if ( str_starts_with ( $string , ‘The’ )) echo «The string starts with ‘The’\n» ;
>

if ( str_starts_with ( $string , ‘the’ )) echo ‘The string starts with «the»‘ ;
> else echo ‘»the» was not found because the case does not match’ ;
>

The above example will output:

The string starts with 'The' "the" was not found because the case does not match

Notes

Note: This function is binary-safe.

See Also

• str_contains() — Determine if a string contains a given substring
• str_ends_with() — Checks if a string ends with a given substring
• stripos() — Find the position of the first occurrence of a case-insensitive substring in a string
• strrpos() — Find the position of the last occurrence of a substring in a string
• strripos() — Find the position of the last occurrence of a case-insensitive substring in a string
• strstr() — Find the first occurrence of a string
• strpbrk() — Search a string for any of a set of characters
• substr() — Return part of a string
• preg_match() — Perform a regular expression match

User Contributed Notes 2 notes

With credit to Paul Phillips for the original polyfill posted.

If you do not have PHP 8, you can use these functions to get the capability of the new string functions.

But! Remember to use a conditional check to make sure the function is not already defined.

// source: Laravel Framework
// https://github.com/laravel/framework/blob/8.x/src/Illuminate/Support/Str.php
if (! function_exists ( ‘str_starts_with’ )) function str_starts_with ( $haystack , $needle ) return (string) $needle !== » && strncmp ( $haystack , $needle , strlen ( $needle )) === 0 ;
>
>
if (! function_exists ( ‘str_ends_with’ )) function str_ends_with ( $haystack , $needle ) return $needle !== » && substr ( $haystack , — strlen ( $needle )) === (string) $needle ;
>
>
if (! function_exists ( ‘str_contains’ )) function str_contains ( $haystack , $needle ) return $needle !== » && mb_strpos ( $haystack , $needle ) !== false ;
>
>
?>

This keeps it from breaking in case you upgrade and forget that you added it. This is a good practice generally when using the global scope for your helper functions.

In PHP7 you may want to use:

if (!function_exists(‘str_starts_with’)) function str_starts_with($str, $start) return (@substr_compare($str, $start, 0, strlen($start))==0);
>
>

AFAIK that is binary safe and doesn’t need additional checks.

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Check if a String Starts With a Specified String in PHP

1. Use substr() Function to Check if a String Starts With a Specified String in PHP
2. Use strpos() Function to Check if a String Starts With a Specified String in PHP
3. Use strncmp() Function to Check if a String Starts With a Specified String in PHP

In this article, we will introduce methods to check if a string starts with a specified string in PHP.

Use substr() Function to Check if a String Starts With a Specified String in PHP

The built-in function substr() is used to access a substring. The string is passed as an input, and the substring that we want to access is returned. We can use this function to check if a string starts with a specific string. The correct syntax to use this function is as follows

substr($string, $startPosition, $lengthOfSubstring); 

php  $string = "Mr. Peter";  if(substr($string, 0, 3) === "Mr.")  echo "The string starts with the desired substring.";  >else  echo "The string does not start with the desired substring."; ?> 

In the above code, we want to check if our string starts with Mr. .

0 is the start index of the substring, or in other words, the substring starts from the first character of the given string.

3 means the length of the returned substring is 3.

If the start of the string is the same as Mr. then it will display The string starts with the desired substring. .

The string starts with the desired substring. 

Use strpos() Function to Check if a String Starts With a Specified String in PHP

The function strpos() returns the position of the first occurrence of a substring in the given string . We could use it to check if a string starts with a specified string.

If the returned value is 0 , it means the given string starts with the specified substring. Otherwise, the string doesn’t start with the checked substring.

strpos() is a case sensitive function. The correct syntax to use this function is as follows.

strpos($string, $searchString, $startPosition); 

php  $string = "Mr. Peter";  if(strpos( $string, "Mr." ) === 0)  echo "The string starts with the desired substring.";  >else  echo "The string does not start with the desired substring."; ?> 

Here, we have checked if our string starts with Mr. by finding the first occurrence of Mr. .

The string starts with the desired substring. 

Use strncmp() Function to Check if a String Starts With a Specified String in PHP

The built-in function strncmp() compares two given strings . This function is also case sensitive. The correct syntax to use this function is as follows.

strncmp($string1, $string2, $length); 

It returns zero if both the strings are equal. This is a case sensitive function.

php  $string = "Mr. Peter";  if(strncmp($string, "Mr.", 3) === 0)  echo "The string starts with the desired substring.";  >else  echo "The string does not start with the desired substring."; ?> 

Here, the two strings are compared. The length of the strings to be compared is three.

The string starts with the desired substring. 

The case insensitive version of strncmp is strncasecmp . It compares the first n characters of the given two strings regardless of their cases.

php  $string = "mr. Peter";  if(strncasecmp($string, "Mr.", 3) === 0)  echo "The string starts with the desired substring.";  >else  echo "The string does not start with the desired substring."; ?> 

The string starts with the desired substring. 

Related Article — PHP String

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