PHP：如何从字符串中删除最后一个单词？

Question

How can I remove, with PHP, the last word from a String?

For example the string "Hi, I'm Gian Marco" would become "Hi, I'm Gian" .

Answer 1

try with this :

$txt = "Hi, I'm Gian Marco";
$str= preg_replace('/\W\w+\s*(\W*)$/', '$1', $txt);
echo $str

out put

Hi, I'm Gian

Answer 2

check this

 <?php
$str ='"Hi, I\'m Gian Marco" will be "Hi, I\'m Gian"';
$words = explode( " ", $str );
array_splice( $words, -1 );

echo implode( " ", $words );
?>

source : Remove last two words from a string

Answer 3

You can do it with regular expression. (see answer of Ahmed Ziani. )

However, in PHP you can also do it using some inbuilt function. see the code below

$text = "Hi, I'm Gian Marco";
$last_space_position = strrpos($text, ' ');
$text = substr($text, 0, $last_space_position);
echo $text;

Answer 4

The current solution is ok if you do not know the last word and the string length is short.

In case you do know it, for instance when looping a concat string for a query like this:

        foreach ($this->id as $key => $id) {
            $sql.=' id =' . $id . ' OR ';
        }

A better solution:

        $sql_chain = chop($sql_chain," OR ");

Be aware that preg_replace with a regex is VERY slow with long strings. Chop is 100 times faster in such case and perf gain can be substantial.

Answer 5

This code may help you :

$str="Hi, I'm Gian Marco";

$split=explode("",$str);
$split_rem=array_pop($split);
foreach ($split as $k=>$v)
{
   echo $v.'';
}

Answer 6

The regular exprerssion can cause issues when the string has special characters. Why not simply go with this:

$input = "Hi, I'm Gian Marco";
$output = substr($input, 0, strrpos($input, " "));
echo $output;

Answer 7

Explode the str with explode(delimiter, string) into an array $words , take the first word put it into $res , and iterate over words the count of $words times minus one which is exclude the last word.

$str = "Hi, I'm Gian Marco";
$words = explode(" ",$str);
$res = $words[0];
for ($i=1; $i < count($words) - 1; $i++) { 
    $res .= ' '.$words[$i]; // concatenation with a space.
}
echo $res; // Hi, I'm Gian

Answer 8

In search for ltrim and rtrim alternatives (to trim a whole first/last word) I came across posts like these. Just want to share the functions I wrote when any other is landing here like I did.

Find the first occurrence of a given word and if it is the first word, return the sentence without that first word.

function leftStrTrim($sentence, $word){    
  $wordLength = strlen($word);
  $wordStart = strpos($sentence, $word);    
  if($wordStart!==false && $wordStart==0){
    return substr($sentence, $wordLength);
  }
  return $sentence;    
}

Find the last occurrence of a given word and if it is the last word, return the sentence without that last word.

function righStrTrim($sentence, $word){    
  $wordLength = strlen($word);
  $wordStart = strrpos($sentence, $word);    
  if($wordStart!==false && $wordStart == strlen($sentence)-$wordLength){
    return substr($sentence, 0, $wordLength*-1);
  }
  return $sentence;    
}