Question

页: 1 我的索引编号为9(此处为e),我将不得不在两个之间打上。我不知道第一点点离指数有多远,也不知道第二点是多少。因此,在营地中这样做是没有任何容易的方法? 另有许多<代码>:s in the string ex. a.b.c.d.something.d.c.b.a

其他几个例子:

bef.ore.something.af.t.erindex: 12 = someth

bef.ore.something.af.t.erindex: 5 = ore<>code>



bef.ore.something.af.t.erindex: 19 = af

Answer 1

作为起点,你可以尝试:

$input =  a.b.something.c.def ;
$index = 9;
$delimiter =  . ;

/*
 * get length of input string
 */
$len = strlen($input);

/*
 * find the index of the first delimiter *after* the index
 */
$afterIdx = strpos($input, $delimiter, $index);

/*
 * find the index of the last delimiter *before* the index 
 * figure out how many characters are left after the index and negate that - 
 * this makes the function ignore that many characters from the end of the string,
 * effectively inspecting only the part of the string up to the index
 * and add +1 to that because we are interested in the location of the first symbol after that
 */
$beforeIdx = strrpos($input, $delimiter, -($len - $index)) + 1; 

/*
 * grab the part of the string beginning at the last delimiter 
 * and spanning up to the next delimiter
 */
$sub = substr($input, $beforeIdx, $afterIdx - $beforeIdx);
echo $sub;

注:至少,如果在指数之前/之后没有文号,则需要增加一些疗效检查。

Answer 2

定期表达是你的朋友:

$regex =  /.?([w]+)/ ;
$string =  a.b.c.d.something.d.c.b.a ;
preg_match_all($regex, $string, $result);
print_r($result[1]);

Note: If your looking for a specific word, just replace [w]+ with the word your looking for.

@19greg96 我看到你现在想要做些什么,对DCoder的榜样采取的一种替代但简单的做法就是:

$string =  a.b.something.d.c.b.a ;
$index = 9;
$delimiter =  . ;

$last_index = strpos($string, $delimiter, $index);
$substr = substr($string, 0, $last_index);
$substr = substr($substr, strrpos($substr, $delimiter) + 1);
echo $substr;

Answer 3

挖掘成阵列,并通过旁边传:

$str= a.b.c.d.something.d.c.b.a ;
$parts=explode( . ,$str);
foreach($parts as $part) {
    if($part== something ) {
        echo( Found it! );
        break;
    }
}

友情链接