之前为项目赶进度用php 的simplexml来解析 xml, 当时发现 simplexml不支持<![CDATA标签， 所有处于这个标签内的值都没有办法取到  

当时在网上找了一个CDATA的转换器， 修改之后， 将CDATA标签给过滤掉。如下

复制代码 代码如下:
 // States:
        //
        //     'out'
        //     '<'
        //     '<!'
        //     '<!['
        //     '<![C'
        //     '<![CD'
        //     '<![CDAT'
        //     '<![CDATA'
        //     'in'
        //     ']'
        //     ']]'
        //
        // (Yes, the states a represented by strings.)
        //
        $state = 'out';
        $a = str_split($xml);
        $new_xml = '';
        foreach ($a AS $k => $v) {
            // Deal with "state".
            switch ( $state ) {
                case 'out':
                    if ( '<' == $v ) {
                        $state = $v;
                    } else {
                        $new_xml .= $v;
                    }
                break;
                case '<':
                    if ( '!' == $v  ) {
                        $state = $state . $v;
                    } else {
                        $new_xml .= $state . $v;
                        $state = 'out';
                    }
                break;
                 case '<!':
                    if ( '[' == $v  ) {
                        $state = $state . $v;
                    } else {
                        $new_xml .= $state . $v;
                        $state = 'out';
                    }
                break;
                case '<![':
                    if ( 'C' == $v  ) {
                        $state = $state . $v;
                    } else {
                        $new_xml .= $state . $v;
                        $state = 'out';
                    }
                break;
                case '<![C':
                    if ( 'D' == $v  ) {
                        $state = $state . $v;
                    } else {
                        $new_xml .= $state . $v;
                        $state = 'out';
                    }
                break;
                case '<![CD':
                    if ( 'A' == $v  ) {
                        $state = $state . $v;
                    } else {