C# 获取临时素材

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Data.SqlClient;
using System.Web;
using System.Web.UI;
using System.Web.UI.WebControls;
using System.IO;
using System.Xml;
using System.Net;


public partial class ssss : System.Web.UI.Page
{
    protected void Page_Load(object sender, EventArgs e)
    {
        Save_Photo();
    }

    protected void Save_Photo()
    {
        try
        {
            string media_id = SSRequest.GetFormString("media_id");
            string[] data = media_id.Split(',');
            string returnda = "{"success":"true","data":[";
            string aaa = "";
            string fileName = PublicMethod.GetUserIdByWxId(urlkey.GetCookie("wzcookie", "opid"));
            Directory.CreateDirectory("绝对路径" + fileName + "");
            for (int i = 0; i < data.Length; i++)
            {
                //文件重命名
                string reName = DateTime.Now.ToString("yyyMMddHHmmssfff");
                string url = "https://api.weixin.qq.com/cgi-bin/media/get?access_token=" + WXHelper.ACCESS_TOKEN(peizhi.appid(), peizhi.appsecret()) + "&media_id=" + data[i];
                WebClient mywebclient = new WebClient();
                //下载文件到本地
                mywebclient.DownloadFile(url, Utils.GetMapPath("/uploadfile/" + fileName + "/" + reName + ".jpg"));

                string str = reName + ".jpg";

                if (i + 1 == data.Length)
                {
                    aaa += """ + str + """;
                }
                else
                {
                    aaa += """ + str + "",";
                }

            }
            returnda += aaa+"]}";

            Response.Write(returnda);
            return;
        }
        catch (Exception ex)
        {
            Log.WriteLogERR(ex);
            return;
        }
    }
    /// <summary>
    /// 用户返回AJAX请求实体 success 是否成功 msg 提示信息 
    /// </summary>
    /// <param name="success"></param>
    /// <param name="msg"></param>
    /// <param name="size"></param>
    protected string JsonStr(bool success, string msg,string size)
    {
        return "{"success":"" + success.ToString().ToLower() + "","msg":"" + msg + "","size":"" + size + ""}";
    }
}