swfUpload 传递参数有有三种形式
1、在url后加连接：
upload_url: "<%=basePath%>upload?action=up",
post_params: {"hello" : "Here I Am","name" : "张三","ff" : document.getElementById("tf").value},use_query_string : true,//要传递参数用到的配置addPostParam("myFileName",encodeURI(file.name));//这个是我用来传递文件名称的