前言

最近开发遇到后端生成图片时英文的换行

贴代码

/* * 字符串相关处理 */class StringUtils{    /**     * 英文字符串换行     * 如果是字母，并且到了换行的地方，则需要看这个字符的下一个字符是否是字母，如果是的话就需要回到上一个不是字母的地方     * 注意：中文和英文     */    public static function wrap($str, $max_len) {        $arr = [];        $len = mb_strlen($str);        if ($len == 0) {            return $arr;        }        if ($len <= $max_len) {            $arr[] = $str;            return $arr;        }        $w_len = 0;        $w_str = "";        $last_index = 0; // 上一次出现不是字母的索引位置        for ($i = 0; $i < $len; $i++) {            $sub_str = mb_substr($str, $i, 1); //将单个字符存到数组当中            $w_str .= $sub_str;            $w_len++;            if (!self::isWord($sub_str)) {                // 记录最后一次出现不是字母的索引                $last_index = $w_len;            }            // 需要换行            if ($w_len >= $max_len) {                if (self::isWord($sub_str)) {                    $w_str_1 = mb_substr($w_str, 0, $last_index);                    $w_str_2 = mb_substr($w_str, $last_index, $w_len);                    $w_len = $w_len - $last_index;                } else {                    $w_str_1 = $w_str;                    $w_str_2 = "";                    $w_len = 0;                }                $arr[] = $w_str_1;                $w_str = $w_str_2;                $last_index = 0;            }        }        $arr[] = $w_str;        return $arr;    }    /**     * 中文换行     */    public static function wrapCh($str, $max_len) {        $arr = [];        $len = mb_strlen($str);        if ($len == 0) {            return $arr;        }        if ($len <= $max_len) {            $arr[] = $str;            return $arr;        }        $page = ceil($len / $max_len);        for ($i = 0; $i < $page; $i++) {            $temp_str = mb_substr($str, $i * $max_len, $max_len);            $arr[] = $temp_str;        }        return $arr;    }    /**     * 判断是否单词     */    public static function isWord($chr) {        $wordArr = ["a","b","c","d","e","f","g","h","i","j","k","l","m","n","o","p","q","r","s","t","u","v","w","x","y","z","A","B","C","D","E","F","G","H","I","J","K","L","M","N","O","P","Q","R","S","T","U","V","W","X","Y","Z"];        return in_array($chr, $wordArr);    }}

执行效果

    // 字符串    $str = "呵呵呵发链接The British Charles Babbage was the inventor of an analytical machine with附加费两款手机 punch发vvvvv个版本发vv cards, and of a difference engine, both forerunners of the computer, and his name is given to the mwei or picoether, 10 to the -12 ether.";    $arr = StringUtils::wrapCh($str , 20);    echo "<br/>暴力换行<br/><br/>";    foreach($arr as $k=>$v){        echo $v . "<br/>";    }    $arr = StringUtils::wrap($str , 20);    echo "<br/>正确的换行<br/><br/>";    foreach($arr as $k=>$v){        echo $v . "<br/>";    }

打印结果

暴力换行呵呵呵发链接The British Charles Babbage was the inventor of an analytical machine with附加费两款手机 punch发vvvvv个版本发vv cards, and of a difference engine,both forerunners ofthe computer, and his name is given to the mwei or picoether, 10 to the -12 ether.正确的换行呵呵呵发链接The British Charles Babbage was the inventor of an analytical machine with附加费两款手机 punch发vvvvv个版本发vv cards, and of a difference engine, both forerunners of the computer, and his name is given to the mwei or picoether, 10 to the -12 ether.