jquery.fileupload.js插件使用--前台上传预览辅助插件类

<?php
/**
* 前台上传文件预览辅助插件类
*
*/
class upload_plugin_class {
/**
* 输出上传一个文件的前台代码
*
* @param String $accept_upload_ajax_url: 响应上传ajax的url地址
* @param String $file_type: image/video
* @param String $old_src: 已有的文件地址
* @return String $str
*/
public static function get_upload_one_file_html($accept_upload_ajax_url='',$file_type='',$old_src='') {
//检查参数
$accept_upload_ajax_url = $accept_upload_ajax_url=='' ? 'accept_all_type_one.php' : $accept_upload_ajax_url;
$file_type = $file_type=='' ? 'image' : $file_type;
//设置一个唯一标识
$sign = time().mt_rand(100000,999999);
//设置返回代码存放变量
$str = "";
$str .= '<script src="jquery.fileupload.js"></script>';
$str .= '<script src="jquery.xdr-transport.js"></script>';
//输入框
$str .= "<input id='upload_file_$sign' type='file' name='upload_file_$sign' />";
//上传进度显示
$str .= "   <div id='upload_status_$sign' style='margin-top:10px;'></div>";
//上传进度条
$str .= "   <div id='upload_bar_$sign' style='margin-top:10px;margin-bottom:10px;height:10px;max-width:200px;background:green;width:0%;'></div>";
//预览框
$str .= "<div id='upload_preview_$sign'>";
//若数据库里有文件地址，则直接显示
if(!empty($old_src)) {
if($file_type == 'image') {
$str .= "<img src='$old_src'/>";
}
if($file_type == 'video') {
$str .= "<embed src='$old_src' allowscriptaccess='always' allowfullscreen='true' wmode='opaque' width='200' height='200'></embed>";
}
}
$str .= "</div>";
//下面是js代码:
$str .= "<script type='text/javascript'>";
$str .= "   $('#upload_file_$sign').fileupload({";
$str .= "       url:'$accept_upload_ajax_url',";
$str .= "       dataType:'json',";
$str .= "       done:function(e,data){";
//上传成功：
$str .= "           if(data.result.sta){";
$str .= "               $('#upload_preview_$sign').html(";
if($file_type == 'image') {//图片预览
$str .= "                   '<img src=\"'+data.result.preview_src+'\"/>'";
} elseif($file_type == 'video') {//视频或音频预览
$str .= "                   '<embed src=\"'+data.result.preview_src+'\" allowscriptaccess=\"always\" allowfullscreen=\"true\" wmode=\"opaque\" width=\"200\" height=\"200\"></embed>'";
}
$str .= "               );";
$str .= "           } else {";
//上传失败
$str .= "               $('#upload_bar_$sign').css('width','0%');";
$str .= "               $('#upload_status_$sign').html('<span style=\"color:red;\">'+data.result.msg+'</span>');";
$str .= "           }";
$str .= "       },";
//上传进度
$str .= "       progress: function (e, data) {";
$str .= "           var progress = parseInt(data.loaded / data.total * 100, 10);";
$str .= "           $('#upload_bar_$sign').css('width', progress + '%');";
$str .= "               $('#upload_status_$sign').html('上传进度：'+progress+'%');";
$str .= "       }";
$str .= "   });";
$str .= "</script>";
return $str;
}

}