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asp.net 自訂控制項實現無重新整理上傳圖片,立即顯示縮圖,儲存圖片縮圖

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點擊瀏覽,選擇圖片之後,右面顯示圖片

第一步:

建立CtFileUpLoad.ascx

複製代碼 代碼如下:<%@ Control Language="C#" AutoEventWireup="true" CodeFile="CtFileUpLoad.ascx.cs"
Inherits="WebParts_CtFileUpLoad" %>
<table cellpadding="0" cellspacing="0">
<tr>
<td>
<iframe src="/WebParts/FileUpLoad.aspx?<%=ParsValue %>" width="240px" height="22px" frameborder="0" scrolling="no"></iframe>
</td>
<td>
<asp:TextBox runat="server" ID="tbFileName" style="display:none"></asp:TextBox>
<div id="dvImg" runat="server" style="position:absolute; margin-left:50px;">
</div>
</td>
</tr>
</table>
<script language="javascript">
function <%=ClientID %>CallLoaded()
{
<% =OnLoaded %>;
}
</script>

複製代碼 代碼如下:using System;
using System.Collections;
using System.Configuration;
using System.Data;
using System.Web;
using System.Web.Security;
using System.Web.UI;
using System.Web.UI.HtmlControls;
using System.Web.UI.WebControls;
using System.Web.UI.WebControls.WebParts;
using System.Drawing;
public partial class WebParts_CtFileUpLoad : System.Web.UI.UserControl
{
public bool AutoFileName
{
get
{
object ob = ViewState[ClientID + "AutoFileName"];
if (ob == null)
ob = true;
return (bool)ob;
}
set
{
ViewState[ClientID + "AutoFileName"] = value;
}
}
public string UpLoadPath
{
get
{
object ob = ViewState[ClientID + "UpLoadPath"];
if (ob == null)
ob = "UPLOADFILES";
return ob.ToString();
}
set
{
ViewState[ClientID + "UpLoadPath"] = value;
}
}
public string OnLoaded
{
get
{
object ob = ViewState[ClientID + "OnLoaded"];
if (ob == null)
ob = "";
return ob.ToString();
}
set
{
ViewState[ClientID + "OnLoaded"] = value;
}
}
public string SupportExtension
{
get
{
object ob = ViewState[ClientID + "SupportExtension"];
if (ob == null)
{
ob = "gif|png|jpeg|jpg";
}
return ob.ToString();
}
set
{
ViewState[ClientID + "SupportExtension"] = value.Replace(".", "");
}
}
public bool ShowImg
{
get
{
object ob = ViewState[ClientID + "ShowImg"];
if (ob == null)
ob = true;
return (bool)ob;
}
set
{
if ((bool)value)
dvImg.Style["display"] = "block";
else
dvImg.Style["display"] = "none";
}
}
public string FileName
{
get
{
return tbFileName.Text;
}
}
protected string ParsValue = "";
protected void Page_Load(object sender, EventArgs e)
{
ParsValue = "AutoFileName=" + AutoFileName.ToString() + "&SupportExtension=" + SupportExtension + "&UpLoadPath=" + UpLoadPath
+ "&ID=" + ClientID;
}
}

第二步:
建立FileUpLoad.aspx 複製代碼 代碼如下:<%@ Page Language="C#" AutoEventWireup="true" CodeFile="FileUpLoad.aspx.cs" Inherits="WebParts_FileUpLoad" %>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head runat="server">
</head>
<body style="margin:0px;">
<form id="form1" runat="server">
<div>
<asp:FileUpload runat="server" ID="FileUpload1" onchange="upload(this);" />
<asp:Button runat="server" ID="btUp" style="display:none" OnClick="btUp_Click" />
</div>
</form>
</body>
</html>
<script language="javascript">
function upload(ob)
{
var expStr=/.*(<%=SupportExtension%>)$/i;
if(!expStr.test(ob.value))
{
alert("上傳檔案類型有誤。\n(支援檔案類型：<%=SupportExtension%>)");
}
else
{
var btUp=document.getElementById("<%=btUp.ClientID %>");
btUp.click();
}
}
</script>

複製代碼 代碼如下:using System;
using System.Collections;
using System.Configuration;
using System.Data;
using System.Web;
using System.Web.Security;
using System.Web.UI;
using System.Web.UI.HtmlControls;
using System.Web.UI.WebControls;
using System.Web.UI.WebControls.WebParts;
using System.Drawing;
using System.IO;
public partial class WebParts_FileUpLoad : System.Web.UI.Page
{
protected string SupportExtension = "";
protected string UpLoadPath = "";
protected bool AutoFileName;
protected string ParentID = "";
protected void Page_Load(object sender, EventArgs e)
{
SupportExtension = Request.QueryString["SupportExtension"];
UpLoadPath = Request.QueryString["UpLoadPath"];
AutoFileName = bool.Parse(Request.QueryString["AutoFileName"].ToString());
ParentID = Request.QueryString["ID"].ToString();
}
protected void btUp_Click(object sender, EventArgs e)
{
Boolean fileOK = false;
if (FileUpload1.HasFile)
{
String fileExtension =
System.IO.Path.GetExtension(FileUpload1.FileName).ToLower();
String[] allowedExtensions = SupportExtension.Split(new string[] { "|" }, StringSplitOptions.RemoveEmptyEntries);
for (int i = 0; i < allowedExtensions.Length; i++)
{
if (fileExtension == "." + allowedExtensions[i])
{
fileOK = true;
}
}
if (fileOK)
{
string path = "";
string name = "";
string sPath = "";
if (AutoFileName)
{
name = DateTime.Now.Ticks.ToString() + System.IO.Path.GetExtension(FileUpload1.FileName).ToLower();
}
else
{
name = FileUpload1.FileName;
}
sPath = Request.PhysicalApplicationPath + "\\" + UpLoadPath + "\\";
path = sPath + name; //圖片地址
string fileName = name; //檔案名稱
string fileName_s = "s_" + name; //縮圖檔案名稱
try
{
//FileInfo file = new FileInfo(name);
// string fileContentType = FileUpload1.PostedFile.ContentType;
//string name = FileUpload1.PostedFile.FileName;//用戶端檔案路徑
//string fileName_sy = "sy_" + file.Name; //浮水印圖檔案名稱(文字)
//string fileName_syp = "syp_" + file.Name;//浮水印圖檔案名稱(圖片)
//string webFilePath = Server.MapPath(UpLoadPath + "\\" + fileName);
//string webFilePath_s = Server.MapPath(UpLoadPath + "\\" + fileName_s);
string webFilePath = sPath + fileName;//伺服器端檔案路徑
string webFilePath_s = sPath + fileName_s;//伺服器端縮圖路徑

if (!File.Exists(webFilePath))
{
if (FileUpload1.PostedFile.ContentLength < 2 * 1024 * 1024) //如果圖片小於2M
{
try
{
FileUpload1.SaveAs(path); //使用saveAS方法儲存檔案
System.Drawing.Image image = System.Drawing.Image.FromFile(path);
if (image.Width > 800 || image.Height > 600)
{
MakeThumbnail(webFilePath, webFilePath_s, 800, 600, "W");//產生縮圖的方法
}
else
{
MakeThumbnail(webFilePath, webFilePath_s, 300, 230, "W");//產生縮圖的方法
}
image.Dispose();
// AddShuiYinWord(webFilePath, webFilePath_sy); //儲存浮水印文字圖片
// AddShuiYinPic(webFilePath, webFilePath_syp, webFilePath_sypf);//儲存添加浮水印圖片之後的圖片
//MakeThumbnail(webFilePath, webFilePath_s, 400, 300, "W");//產生縮圖的方法

Page.RegisterClientScriptBlock("succcess", @"<script>
alert('上傳成功');
parent.document.getElementById('" + ParentID + "_" + "tbFileName" + @"').value='" + fileName_s + @"';
</script>");
}
catch (Exception ex)
{
Page.RegisterClientScriptBlock("err", "<script>alert('提示：檔案上傳失敗，失敗原因：：" + ex.Message + "');</script>");
}
}
else
{
Page.RegisterClientScriptBlock("err", "<script>alert('提示：圖片不能大於2M');</script>");
}
}
else
{
this.Page.RegisterClientScriptBlock("err", "<script>alert('圖片重複');</script>");
}
}
catch (System.Exception err)
{
this.Page.RegisterClientScriptBlock("err", "<script>alert('" + err.Message + "');</script>");
}
try
{
Bitmap bmp = new Bitmap(path);
int width = 0, height = 0;
int dvalue = 200;
if (bmp.Width < dvalue & bmp.Height < 200)
{
width = bmp.Width;
height = bmp.Height;
}
else if (bmp.Width > bmp.Height)
{
width = dvalue;
height = dvalue * (bmp.Width / bmp.Height);
}
else
{
height = dvalue;
width = dvalue * (bmp.Height / bmp.Width);
}
this.Page.RegisterClientScriptBlock("show", @"<script>
parent.VarValue='" + UpLoadPath + "/" + fileName_s + "';" +
"parent." + ParentID + "CallLoaded();" +
"parent.document.getElementById('" + ParentID + "_" + "dvImg" + @"').innerHTML=""" +
"<img src='http://www.jb51.net/" + UpLoadPath + "/" + fileName_s + "' style='width:" + width.ToString() + "px; height:" + height + "px;'/>" + @""";
</script>");
bmp.Dispose();
}
catch
{
}
finally
{
//****判斷該檔案是否存在,如果存在,則刪除圖片
if (File.Exists(path))
{
//****刪除使用者用戶端上傳的圖片,伺服器上只儲存縮減之後的圖片
File.Delete(path);
}
}
}
else
{
this.Page.RegisterClientScriptBlock("err", "<script>alert('error');</script>");
}
}
}
/// <summary>
/// 產生縮圖
/// </summary>
/// <param name="originalImagePath">源圖路徑（實體路徑）</param>
/// <param name="thumbnailPath">縮圖路徑（實體路徑）</param>
/// <param name="width">縮圖寬度</param>
/// <param name="height">縮圖高度</param>
/// <param name="mode">產生縮圖的方式</param>
public void MakeThumbnail(string originalImagePath, string thumbnailPath, int width, int height, string mode)
{
System.Drawing.Image originalImage = System.Drawing.Image.FromFile(originalImagePath);
int towidth = width;
int toheight = height;
int x = 0;
int y = 0;
int ow = originalImage.Width;
int oh = originalImage.Height;
switch (mode)
{
case "HW"://指定高寬縮放（可能變形）
break;
case "W"://指定寬，高按比例
toheight = originalImage.Height * width / originalImage.Width;
break;
case "H"://指定高，寬按比例
towidth = originalImage.Width * height / originalImage.Height;
break;
case "Cut"://指定高寬裁減（不變形）
if ((double)originalImage.Width / (double)originalImage.Height > (double)towidth / (double)toheight)
{
oh = originalImage.Height;
ow = originalImage.Height * towidth / toheight;
y = 0;
x = (originalImage.Width - ow) / 2;
}
else
{
ow = originalImage.Width;
oh = originalImage.Width * height / towidth;
x = 0;
y = (originalImage.Height - oh) / 2;
}
break;
default:
break;
}
//建立一個bmp圖片
System.Drawing.Image bitmap = new System.Drawing.Bitmap(towidth, toheight);
//建立一個畫板
System.Drawing.Graphics g = System.Drawing.Graphics.FromImage(bitmap);
//設定高品質插值法
g.InterpolationMode = System.Drawing.Drawing2D.InterpolationMode.High;
//設定高品質,低速度呈現平滑程度
g.SmoothingMode = System.Drawing.Drawing2D.SmoothingMode.HighQuality;
//清空畫布並以透明背景色填充
g.Clear(System.Drawing.Color.Transparent);
//在指定位置並且按指定大小繪製原圖片的指定部分
g.DrawImage(originalImage, new System.Drawing.Rectangle(0, 0, towidth, toheight),
new System.Drawing.Rectangle(x, y, ow, oh),
System.Drawing.GraphicsUnit.Pixel);
try
{
//以jpg格式儲存縮圖
bitmap.Save(thumbnailPath, System.Drawing.Imaging.ImageFormat.Jpeg);
}
catch (System.Exception e)
{
throw e;
}
finally
{
originalImage.Dispose();
bitmap.Dispose();
g.Dispose();
}
}
/// <summary>
/// 在圖片上增加文字浮水印
/// </summary>
/// <param name="Path">原伺服器圖片路徑</param>
/// <param name="Path_sy">產生的帶文字浮水印的圖片路徑</param>
protected void AddShuiYinWord(string Path, string Path_sy)
{
string addText = "http://www.jb51.net";
System.Drawing.Image image = System.Drawing.Image.FromFile(Path);
System.Drawing.Graphics g = System.Drawing.Graphics.FromImage(image);
g.DrawImage(image, 0, 0, image.Width, image.Height);
System.Drawing.Font f = new System.Drawing.Font("Verdana", 16);
System.Drawing.Brush b = new System.Drawing.SolidBrush(System.Drawing.Color.Blue);
g.DrawString(addText, f, b, 15, 15);
g.Dispose();
image.Save(Path_sy);
image.Dispose();
}
/// <summary>
/// 在圖片上產生圖片浮水印
/// </summary>
/// <param name="Path">原伺服器圖片路徑</param>
/// <param name="Path_syp">產生的帶圖片浮水印的圖片路徑</param>
/// <param name="Path_sypf">浮水印圖片路徑</param>
protected void AddShuiYinPic(string Path, string Path_syp, string Path_sypf)
{
System.Drawing.Image image = System.Drawing.Image.FromFile(Path);
System.Drawing.Image copyImage = System.Drawing.Image.FromFile(Path_sypf);
System.Drawing.Graphics g = System.Drawing.Graphics.FromImage(image);
g.DrawImage(copyImage, new System.Drawing.Rectangle(image.Width - copyImage.Width, image.Height - copyImage.Height, copyImage.Width, copyImage.Height), 0, 0, copyImage.Width, copyImage.Height, System.Drawing.GraphicsUnit.Pixel);
g.Dispose();
image.Save(Path_syp);
image.Dispose();
}
}

屬性:
SupportExtension 自訂上傳的格式,用"|"分隔;
UpLoadPath 　　自訂上傳到伺服器的檔案夾;
AutoFileName　　ture表示根據時間自動組建檔案名,不會重複,false表示原來的圖片名稱,重複會覆蓋.

轉載請註明出處
2009-12-24 18:39:27 by 齊學佳

本文章原先以中文撰寫並發佈於 aliyun.com，亦設英文版本，僅作資訊用途。本網站不對文章的準確性，完整性或可靠性或其任何翻譯作出任何明示或暗示的陳述或保證。如對該文章有任何疑慮或投訴，請傳送電郵至 info-contact@alibabacloud.com 並提供相關疑慮或投訴的詳細說明。職員會於 5 個工作天內與您聯絡，一經驗證之後，即會刪除該侵權內容。

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