


How to Extract a Substring Before the Last Occurrence of a Character in PHP?
Determining Substring before the Last Character Occurrence
Obtaining a substring up to the last instance of a character in a string can be a commonly encountered task in programming. Let's explore a solution in PHP that elegantly addresses this need.
Consider the following scenario. We're given a string, such as "$string = "Hello World Again"." The goal is to extract the portion before the last space character, resulting in "Hello World".
Using the strrchr() function, we can conveniently locate the last occurrence of a specified character within the string. In this case, "strrchr($string, ' ')" would return " Again". However, we need to isolate the desired substring.
The versatile substr() function comes to our rescue. By specifying a starting position of 0 and an ending position determined by strrpos($string, ' '), we can effectively fetch the substring up to the last space occurrence.
For instance, "substr($string, 0, strrpos($string, ' '))" would yield the desired output of "Hello World". This approach ensures that the result effortlessly adapts to the variable string, extracting the substring before the last specified character.
In cases where the character is absent from the string, the substr() function gracefully handles such scenarios. The substring is simply truncated to the beginning of the string, resulting in an empty string being echoed.
The above is the detailed content of How to Extract a Substring Before the Last Occurrence of a Character in PHP?. For more information, please follow other related articles on the PHP Chinese website!

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