Introduction to rtrim

The rtrim function is used to remove whitespace or other specified characters from the end of a string. It stands for "right trim" because it only affects the right (or trailing) end of the string.

Syntax

The syntax for the rtrim function is as follows:

rtrim(string $string, ?string $charlist = " \t\n\r\0\x0B"): string

The function takes two parameters:

1. string: The input string to be trimmed.
2. charlist: An optional parameter specifying which characters to remove. If omitted, the default list of whitespace characters is used.

The function returns the trimmed string.

Examples

Here are some examples of how to use the rtrim function:

// Remove trailing whitespace
$str1 = "Hello World    ";
$str1 = rtrim($str1); // "Hello World"

// Remove trailing specific characters
$str2 = "This is a sentence.";
$str2 = rtrim($str2, "."); // "This is a sentence"

// Remove trailing whitespace and specific characters
$str3 = "   abc.def.   \t";
$str3 = rtrim($str3, ". \t"); // "   abc.def."

Conclusion

The rtrim function is a useful tool for manipulating strings in PHP programs. By removing trailing whitespace or other specified characters, it helps to ensure that strings are properly formatted and ready for further processing.