SWFUpload实现原图及缩略图上传保存清空
1.修改类 Thumbnail
using
System;
using
System.Data;
using
System.Configuration;
using
System.Collections;
using
System.Web;
using
System.Web.Security;
using
System.Web.UI;
using
System.Web.UI.WebControls;
using
System.Web.UI.WebControls.WebParts;
using
System.Web.UI.HtmlControls;
using
System.IO;
using
System.Collections.Generic;
public
partial
class
upload : System.Web.UI.Page
{
protected void Page_Load(object sender, EventArgs e)
{ System.Drawing.Image thumbnail_image = null; System.Drawing.Image original_image = null; System.Drawing.Bitmap final_image = null; System.Drawing.Graphics graphic = null; MemoryStream ms = null; MemoryStream maxms = null; try { // Get the data HttpPostedFile jpeg_image_upload = Request.Files["Filedata"]; // Retrieve the uploaded image original_image = System.Drawing.Image.FromStream(jpeg_image_upload.InputStream); // Calculate the new width and height int width = original_image.Width; int height = original_image.Height; int target_width = 100; int target_height = 75; int new_width, new_height; float target_ratio = (float)target_width / (float)target_height; float image_ratio = (float)width / (float)height; if (target_ratio > image_ratio) { new_height = target_height; new_width = (int)Math.Floor(image_ratio * (float)target_height);
} else { new_height = (int)Math.Floor((float)target_width / image_ratio); new_width = target_width; } new_width = new_width > target_width ? target_width : new_width; new_height = new_height > target_height ? target_height : new_height; // Create the thumbnail // Old way //thumbnail_image = original_image.GetThumbnailImage(new_width, new_height, null, System.IntPtr.Zero); // We don't have to create a Thumbnail since the DrawImage method will resize, but the GetThumbnailImage looks better // I've read about a problem with GetThumbnailImage. If a jpeg has an embedded thumbnail it will use and resize it which // can result in a tiny 40x40 thumbnail being stretch up to our target size final_image = new System.Drawing.Bitmap(target_width, target_height); graphic = System.Drawing.Graphics.FromImage(final_image); graphic.FillRectangle(new System.Drawing.SolidBrush(System.Drawing.Color.Black), new System.Drawing.Rectangle(0, 0, target_width, target_height)); int paste_x = (target_width - new_width) / 2; int paste_y = (target_height - new_height) / 2; graphic.InterpolationMode = System.Drawing.Drawing2D.InterpolationMode.HighQualityBicubic; /* new way */ //graphic.DrawImage(thumbnail_image, paste_x, paste_y, new_width, new_height); graphic.DrawImage(original_image, paste_x, paste_y, new_width, new_height); // Store the thumbnail in the session (Note: this is bad, it will take a lot of memory, but this is just a demo)# ms = new MemoryStream(); //final_image.Save(ms, System.Drawing.Imaging.ImageFormat.Jpeg); final_image.Save(ms, System.Drawing.Imaging.ImageFormat.Jpeg);
修改部分开始 修改部分结束 // Put it all in the Session (initialize the session if necessary) List<Thumbnail> thumbnails = Session["file_info"] as List<Thumbnail>; if (thumbnails == null) { thumbnails = new List<Thumbnail>(); Session["file_info"] = thumbnails; } thumbnails.Add(thumb); Response.StatusCode = 200; Response.Write(thumbnail_id); } catch { // If any kind of error occurs return a 500 Internal Server error Response.StatusCode = 500; Response.Write("An error occured"); Response.End(); } finally { // Clean up if (final_image != null) final_image.Dispose(); if (graphic != null) graphic.Dispose(); if (original_image != null) original_image.Dispose(); if (thumbnail_image!= null )thumbnail_image.Dispose(); if (ms != null) ms.Close(); Response.End(); } }
}
2.修改upload.aspx.cs
using
System;
using
System.Data;
using
System.Configuration;
using
System.Web;
using
System.Web.Security;
using
System.Web.UI.WebControls;
using
System.Web.UI.WebControls.WebParts;
using
System.Web.UI.HtmlControls;
using
System.Web.UI;
/// <summary>/// Summary description for Thumbnail/// </summary>
public
class
Thumbnail
{ public Thumbnail(string id, byte[] data, byte[] minidata) { this.ID = id; this.Data = data; this.miniData = minidata; } private string id; public string ID { get { return this.id; } set { this.id = value; } } private byte[] max_data; public byte[] Data { get { return this.max_data; } set { this.max_data = value; } } private byte[] thumbnail_data; public byte[] miniData { get { return this.thumbnail_data; } set { this.thumbnail_data = value; } } }
3.保存按钮事件
protected
void
btnSave_Click(
object
sender, EventArgs e)
{ if (Session["file_info"] != null) { List<Thumbnail> thumbnails = Session["file_info"] as List<Thumbnail>; string UploadPath = Server.MapPath("~/picupload/"); string strPicName; string strPicMinName; string strCID; strCID = ddlpic.SelectedItem.Value; TArticle CA = new TArticle(); foreach (Thumbnail img in thumbnails) { strPicName = img.ID + ".jpg"; strPicMinName = img.ID + "_mini.jpg"; FileStream fs = new FileStream(UploadPath + img.ID + ".jpg", FileMode.Create); BinaryWriter bw = new BinaryWriter(fs); bw.Write(img.Data); bw.Close(); fs.Close(); FileStream fss = new FileStream(UploadPath + img.ID + "_mini.jpg", FileMode.Create); BinaryWriter bww = new BinaryWriter(fss); bww.Write(img.miniData); bww.Close(); fss.Close(); //共用一个表文章表，原图片使用title,缩略图使用abstract //栏目分类使用状态为0的 CA.ArticleCID = strCID; CA.ArticleTitle = strPicName; CA.ArticleAbstract = strPicMinName; CA.PicInsert(); } Session.Remove("file_info"); Response.Write("<script>alert('图片上传成功！');</script>"); } }
总结：
int target_width = 100; //缩略图宽
int target_height = 75; //缩略图高
1.修改类Thumbnail，添加缩略图成员
2.修改上传控件,创建内存流存储缩略图数据流
3.上传保存，从Thumbnail类中读取数据流，使用文件流保存图片
并保存到数据库中。