【100分】求多图上传+预览

<%@ WebHandler Language="c#" Class="File_WebHandler" Debug="true" %>



using System;

using System.Web;

using System.IO;

using System.Drawing;

using System.Drawing.Imaging;



public class File_WebHandler : IHttpHandler

{

    public void ProcessRequest(HttpContext context)

    {

        if (context.Request.Files.Count > 0)

        {

            HttpPostedFile file = context.Request.Files[0];



            if (file.ContentLength > 0 && file.ContentType.IndexOf("image/") >= 0)

            {

                int width = Convert.ToInt32(context.Request.Form["width"]);

                int height = Convert.ToInt32(context.Request.Form["height"]);



                string path = "data:image/jpeg;base64," + Convert.ToBase64String(ResizeImg(file.InputStream, width, height).GetBuffer());



                context.Response.Write(path);

            }

        }

    }



    public MemoryStream ResizeImg(Stream ImgFile, int maxWidth, int maxHeight)

    {

        Image imgPhoto = Image.FromStream(ImgFile);

        

        decimal desiredRatio = Math.Min((decimal)maxWidth / imgPhoto.Width, (decimal)maxHeight / imgPhoto.Height);

        int iWidth = (int)(imgPhoto.Width * desiredRatio);

        int iHeight = (int)(imgPhoto.Height * desiredRatio);

        

        Bitmap bmPhoto = new Bitmap(iWidth, iHeight);



        Graphics gbmPhoto = Graphics.FromImage(bmPhoto);

        gbmPhoto.DrawImage(imgPhoto, new Rectangle(0, 0, iWidth, iHeight), new Rectangle(0, 0, imgPhoto.Width, imgPhoto.Height), GraphicsUnit.Pixel);



        MemoryStream ms = new MemoryStream();

        bmPhoto.Save(ms, ImageFormat.Jpeg);



        imgPhoto.Dispose();

        gbmPhoto.Dispose();

        bmPhoto.Dispose();



        return ms;

    }



    public bool IsReusable

    {

        get

        {

            return false;

        }

    }

}

<table class="perview">

	<tr>

		<th align="right"> 选择图片： </th>

		<td width="75%"> <div id="idPicFile"> </div> </td>

	</tr>

	<tr>

		<td colspan="2"><table>

				<thead>

					<tr>

						<th> 文件路径 </th>

						<th width="30%"> 预览图 </th>

						<th width="20%"> 操作 </th>

					</tr>

				</thead>

				<tbody id="idPicList">

					<tr>

						<td></td>

						<td align="center"></td>

						<td align="center"><a href="#">移除</a></td>

					</tr>

				</tbody>

			</table></td>

	</tr>

</table>

<script>



var table = $$("idPicList"), model = table.removeChild(table.rows[0]);



function AddPreview(){

	var file = document.createElement("input"),

		img = document.createElement("img"),

		ip = new ImagePreview( file, img, {

				maxWidth:	150,

				maxHeight:	100,

				action:		"ImagePreview.ashx",

				onErr:		function(){ alert("载入预览出错！"); ResetFile(file); },

				onCheck:	CheckPreview,

				onShow:		ShowPreview

			});

	file.type = "file"; file.name = "pic";

	file.onchange = function(){ ip.preview(); };

	$$("idPicFile").appendChild(file);

}

  System.Text.StringBuilder strMsg = new System.Text.StringBuilder("您输入的用户名是：" + TextBox1.Text + "<br/>");

      strMsg.Append("上传的文件分别是：<hr color='red'/>");

    strMsg.Append("上传的文件类型：" + postedFile.ContentType.ToString() + "<br>");

            strMsg.Append("客户端文件地址：" + postedFile.FileName + "<br>");

            strMsg.Append("上传文件的文件名：" + fileName + "<br>");

            strMsg.Append("上传文件的扩展名：" + fileExtension + "<br><hr>");

我在预览完之后 有个button上传按钮点击事件

string url = "";

        //遍历file表单元素

        HttpFileCollection files = HttpContext.Current.Request.Files;

        for (int iFile = 0; iFile < files.Count; iFile++)

        {

           

            //检查文件扩展名字

            HttpPostedFile postedFile = files[iFile];

            string fileName, fileExtension;

            fileName = System.IO.Path.GetFileName(postedFile.FileName);

            if (fileName != "")

            {

                fileExtension = System.IO.Path.GetExtension(fileName);



                ///'可根据扩展名字的不同保存到不同的文件夹

                ///注意：可能要修改你的文件夹的匿名写入权限。

                string fileUrlPath = "~/admin/computerImgs/";//生成的文件夹要保存的位置

                string time = DateTime.Now.ToString("yyyyMMdd");

                string path = fileUrlPath + time + "/";  //完整路径

                if (!Directory.Exists(Server.MapPath(path)))

                {

                    Directory.CreateDirectory(Server.MapPath(path)); //创建文件夹

                }



                string imgUrl = path + fileName;



                url += imgUrl + "|";



                postedFile.SaveAs(System.Web.HttpContext.Current.Request.MapPath(path) + fileName);

            }

        }