//函数名: compress_html
//参数: $string
//返回值: 压缩后的$string
function compress_html($string) {
    $string = str_replace("\\r\\n", '', $string); //清除换行符
    $string = str_replace("\\n", '', $string); //清除换行符
    $string = str_replace("\\t", '', $string); //清除制表符
    $pattern = array (
                    "/> *([^ ]*) *</", //去掉注释标记
                    "/[\\s]+/",
                    "/<!--[\\\\w\\\\W\\r\\\\n]*?-->/",
                    "/\\" /",
                    "/ \\"/",
                    "'/\\*[^*]*\\*/'"
                    );
    $replace = array (
                    ">\\\\1<",
                    " ",
                    "",
                    "\\"",
                    "\\"",
                    ""
                    );
    return preg_replace($pattern, $replace, $string);
}
//该片段来自于http://yuncode.net