PHP manipulation string function parsing practice
PHP language is a very excellent programming language, widely used in network programming, Web development and other fields. In the PHP language, string manipulation functions are widely used and are a very commonly used function module. This article will introduce some techniques and practical cases of string manipulation functions in PHP.
- String interception
In the PHP language, string interception is a very important operation. PHP provides a variety of string interception functions, such as substr, mb_substr, etc. We can use these functions to intercept any part of the string.
Sample code:
$str = "Hello World!"; $substr = substr($str, 6, 5); //从第6个字符开始截取5个字符 echo $substr; //输出"World"
In the above code, we use PHP's substr function. The first parameter is the string to be intercepted, and the second parameter is the starting point of interception. Position, the third parameter is the intercepted length. String interception operations can be easily implemented using the substr function.
- String replacement
In PHP, we can use the str_replace function to perform string replacement operations. This function finds a specified character or string in a string and replaces it with another character or string.
Sample code:
$str = "Hello World!"; $new_str = str_replace("World", "PHP", $str); //将"World"替换成"PHP" echo $new_str; //输出"Hello PHP!"
In the above code, we use PHP's str_replace function. The first parameter is the string to be replaced, and the second parameter is the character to be replaced. String, the third parameter is the string to be operated on. String replacement operations can be easily implemented using the str_replace function.
- String splitting
In PHP, we can use the explode function to split the string. This function can split a string according to the specified delimiter and return an array.
Sample code:
$str = "Hello World!"; $arr = explode(" ", $str); //按照空格分割字符串 print_r($arr); //输出Array([0] => "Hello", [1] => "World!")
In the above code, we use PHP's explode function. The first parameter is the delimiter, and the second parameter is the string to be operated on. String splitting operations can be easily implemented using the explode function.
- String formatting
In PHP, we can use the printf function to perform string formatting operations. This function can format the specified value according to the specified format and return a string.
Sample code:
$name = "Tom"; $age = 20; printf("My name is %s and I am %d years old.", $name, $age); //输出"My name is Tom and I am 20 years old."
In the above code, we use PHP's printf function. The first parameter is the string to be formatted, and the second parameter starts with the string to be formatted. value. In the string to be formatted, we use two placeholders, %s and %d, to represent strings and integers respectively. The string formatting operation can be easily implemented using the printf function.
- URL encoding and decoding
In PHP, we can use the urlencode and urldecode functions to perform URL encoding and decoding operations. This function can encode or decode special characters in the URL to ensure the correctness of the URL.
Sample code:
$str = "Hello World!"; $url_str = urlencode($str); //URL编码 echo $url_str; //输出"Hello+World%21" $origin_str = urldecode($url_str); //URL解码 echo $origin_str; //输出"Hello World!"
In the above code, we use PHP's urlencode and urldecode functions, the first function is used for URL encoding, and the second function is used for URL decoding. URL encoding and decoding operations can be easily implemented using the urlencode and urldecode functions.
To sum up, the string function in the PHP language is a very powerful and commonly used functional module, which plays an extremely important role in PHP programming. The editor provides several practical cases here for your reference.
The above is the detailed content of PHP manipulation string function parsing practice. For more information, please follow other related articles on the PHP Chinese website!

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