php获取中文拼音首字母类和函数分享

class Helper_Spell {
/**
 * $_pinyins
 * @var array
 * @access private
 */
private $_pinyins = array(
    176161 => 'A',
    176197 => 'B',
    178193 => 'C',
    180238 => 'D',
    182234 => 'E',
    183162 => 'F',
    184193 => 'G',
    185254 => 'H',
    187247 => 'J',
    191166 => 'K',
    192172 => 'L',
    194232 => 'M',
    196195 => 'N',
    197182 => 'O',
    197190 => 'P',
    198218 => 'Q',
    200187 => 'R',
    200246 => 'S',
    203250 => 'T',
    205218 => 'W',
    206244 => 'X',
    209185 => 'Y',
    212209 => 'Z',
    215249 => 'Z',
);

/**
 * $_charset
 * @var string
 * @access private
 */
private $_charset = null;

/**
 * __construct 构造函数, 指定需要的编码 default: utf-8 支持utf-8, gb2312
 *
 * @param unknown_type $charset
 */
public function __construct( $charset = 'utf-8' ) {
    $this->_charset = $charset;
}

/**
 * getInitialsFirst 返回首个汉字的拼音
 *
 * @access public
 * @static
 * @param  string $str
 * @return string
 * @example Helper_Spell::getInitialsFirst('我的爱'); => w
 */
public static function getInitialsFirst( $str, $charset = 'utf-8' ) {
    $chars = array(
        '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');

    $string = self::getInitials( $str );
    $length = strlen($string);

    for($i=0; $i <$length; $i++) {
        if ( in_array( $string{$i}, $chars ) ) {
            return $string{$i};
        }
    }
    return '*';
}

/**
 * getInitials 返回拼音组合
 *
 * @access public
 * @static
 * @param  string $str
 * @return string
 * @example Helper_Spell::getInitials('我的爱'); => wda
 */
public static function getInitials( $str, $charset = 'utf-8' ) {
    $instance = new Helper_Spell( $charset );
    return $instance->_getInitials( $str );
}

/**
 * _getInitials 获取中文字串的拼音首字符
 *              注：英文的字串：不变返回(包括数字)    eg .abc123 => abc123
 *                  中文字符串：返回拼音首字符        eg. 王小明 => WXM
 *                  中英混合串: 返回拼音首字符和英文  eg. 我i我j => WIWJ
 *
 * @access private
 * @param  string $str
 * @return string
 */
private function _getInitials( $str, $translation=TRUE ){
    if ( empty($str) ) return '';
    if ( $this->_isAscii($str[0]) && $this->_isAsciis( $str ))
        return $str;

    if ( $translation )
        $str = Translation_Big2gb::big2gb( $str );

    $result = array();
    if ( $this->_charset == 'utf-8' ){
        //IGNORE很重要，加上这个就可以是ICONV()函数忽略错误，继续执行
        $str = iconv( 'utf-8', 'gbk//IGNORE', $str );
    }
    $words = $this->_cutWord( $str );

    foreach ( $words AS $word ) {          
        if ( $this->_isAscii($word) ) {//非中文
            $result[] = $word;
            continue;
        }
        $code = ( ord(substr($word,0,1)) ) * 1000 + (ord(substr($word,1,1)));
        //获取拼音首字母A--Z

        if ( ($i = $this->_search($code)) != -1 ){
            $result[] = $this->_pinyins[$i];
        }
    }
    return strtoupper(implode('', $result));
}

/**
 * _msubstr 获取中文字符串
 *
 * @access private
 * @param string $str
 * @param int    $start
 * @param int    $len
 * @return string
 */
private function _msubstr ($str, $start, $len) {
    $start  = $start * 2;
    $len    = $len * 2;
    $strlen = strlen($str);
    $result = '';
    for ( $i = 0; $i <$strlen; $i++ ) {
        if ( $i >= $start && $i <($start + $len) ) {
            if ( ord(substr($str, $i, 1)) > 129 ) $result .= substr($str, $i, 2);
            else $result .= substr($str, $i, 1);
        }
        if ( ord(substr($str, $i, 1)) > 129 ) $i++;
    }
    return $result;
}

/**
 * _cutWord  字符串切分为数组 (汉字或者一个字符为单位)
 *
 * @access private
 * @param string $str
 * @return array
 */
private function _cutWord( $str ) {
    $words = array();
    while ( $str != "" ) {
        if ( $this->_isAscii($str) ) {//非中文
            $words[] = $str[0];
            $str = substr( $str, strlen($str[0]) );
        } else {
            $word = $this->_msubstr( $str, 0, 1 );
            $words[] = $word;
            $str = substr( $str,  strlen($word) );
        }
     }
     return $words;
}

/**
 * _isAscii 判断字符是否是ascii字符
 *
 * @access private
 * @param  string $char
 * @return bool
 */
private function _isAscii( $char ) {
    return ( ord( substr($char,0,1) ) <160 );
}

/**
 * _isAsciis 判断字符串前3个字符是否是ascii字符
 *
 * @access private
 * @param  string $str
 * @return bool
 */
private function _isAsciis( $str ) {
    $len = strlen($str) >= 3 ? 3: 2;
    $chars = array();
    for( $i = 1; $i <$len -1; $i++ ){
        $chars[] = $this->_isAscii( $str[$i] ) ? 'yes':'no';
    }
    $result = array_count_values( $chars );
    if ( empty($result['no']) ){
        return true;
    }
    return false;
}

/**
 * _getChar 通过ASC码返回字母或者数字
 *
 * @access private
 * @param  string $ascii
 * @return string
 */
private function _getChar( $ascii ){
    if ( $ascii >= 48 && $ascii <= 57 ) {
        return chr($ascii);  //数字
    } elseif ( $ascii>=65 && $ascii<=90 ) {
        return chr($ascii);   // A--Z
    } elseif ($ascii>=97 && $ascii<=122 ) {
        return chr($ascii-32); // a--z
    } else {
        return '~'; //其他
    }
}

/**
 * _search 查找需要的汉字内码(gb2312) 对应的拼音字符(二分法)
 *
 * @access private
 * @param int $code
 * @return int
 */
private function _search( $code ) {   
    $data = array_keys($this->_pinyins);

    $lower = 0;
    $upper = sizeof($data)-1;

    // 排除非一级汉字
    if ($code <$data[0] || $code > $data[23]) return -1;

    for (;;) {        
        if ( $lower > $upper ){            
            return $data[$lower-1];
        }
        $middle = (int) round(($lower + $upper) / 2);
        if ( !isset($data[$middle]) ) {         
            return -1;
        }

        if ( $data[$middle] <$code ){
            $lower = (int)$middle + 1;
        } else if ( $data[$middle] == $code ) {          
            return $data[$middle];
        } else {
            $upper = (int)$middle - 1;
        }
    }// end for
}

}