form id="form1" runat="server">
asp:FileUpload ID="FileUpload1" runat="server" />
asp:Button ID="Button1" runat="server" Text="上傳" OnClick="Button1_Click" />
asp:Label ID="Label1" runat="server" Text="" Style="color: Red">/asp:Label>
/form>

protected void Button1_Click(object sender, EventArgs e)
{
    if (FileUpload1.HasFile)
    {
    FileUpload1.SaveAs(Server.MapPath("~/") + FileUpload1.FileName);
    Label1.Text = "上傳成功！";
    }
}

form id="form1" runat="server">
input type="file" id="file1" runat="server" />
asp:Button ID="Button1" runat="server" Text="上傳" OnClick="Button1_Click" />
asp:Label ID="Label1" runat="server" Text="" Style="color: Red">/asp:Label>
/form>

protected void Button1_Click(object sender, EventArgs e)
{
    if (file1.PostedFile.ContentLength > 0)
    {
    file1.PostedFile.SaveAs(Server.MapPath("~/") + Path.GetFileName(file1.PostedFile.FileName));
    Label1.Text = "上傳成功！";
    }
}

form id="form1" runat="server" enctype="multipart/form-data">
input type="file" name="file" />
asp:Button ID="Button1" runat="server" Text="上傳" OnClick="Button1_Click" />
asp:Label ID="Label1" runat="server" Text="" Style="color: Red">/asp:Label>
/form>

protected void Button1_Click(object sender, EventArgs e)
{
    if (Request.Files["file"].ContentLength > 0)
    {
    Request.Files["file"].SaveAs(Server.MapPath("~/") + Path.GetFileName(Request.Files["file"].FileName));
    Label1.Text = "上傳成功！";
    }
}

using System;
using System.Data;
using System.Configuration;
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.Drawing;
using System.IO;
using System.Drawing.Imaging;

namespace EC
{
/// summary>
/// 上傳類
/// /summary>
public class UploadObj
{

public UploadObj()
{
//
// TODO: 在此處添加構造函數邏輯
//
}
/// summary>
/// 允許文件上傳的類型枚舉
/// /summary>
public enum FileType
{
jpg,gif,bmp,png
}

#region 取得文件后綴
/// summary>
/// 取得文件后綴
/// /summary>
/// param name="filename">文件名稱/param>
/// returns>/returns>
public static string GetFileExtends(string filename)
{
string ext = null;
if (filename.IndexOf('.') > 0)
{
string[] fs = filename.Split('.');
ext = fs[fs.Length - 1];
}
return ext;
}
#endregion

#region 檢測文件是否合法
/// summary>
/// 檢測上傳文件是否合法
/// /summary>
/// param name="fileExtends">文件后綴名/param>
/// returns>/returns>
public static bool CheckFileExtends(string fileExtends)
{
bool status = false;
fileExtends = fileExtends.ToLower();
string[] fe = Enum.GetNames(typeof(FileType));
for (int i = 0; i fe.Length; i++)
{
if (fe[i].ToLower() == fileExtends)
{
status = true;
break;
}
}
return status;
}
#endregion

#region 保存文件
/// summary>
/// 保存文件
/// /summary>
/// param name="fpath">全路徑,Server.MapPath()/param>
/// param name="myFileUpload">上傳控件/param>
/// returns>/returns>
public static string PhotoSave(string fpath,FileUpload myFileUpload)
{
string s = "";
string fileExtends = "";
string fileName = myFileUpload.FileName;
if (fileName != "")
{
//取得文件后綴
fileExtends = EC.UploadObj.GetFileExtends(fileName);
if (!EC.UploadObj.CheckFileExtends(fileExtends))
{
EC.MessageObject.ShowPre("上傳文件類型不合法");
}
Random rd = new Random();
s = EC.RandomObject.DateRndName(rd) + "." + fileExtends;
string file = fpath + "\" + s;
try
{
myFileUpload.SaveAs(file);
}
catch (Exception ee)
{
throw new Exception(ee.ToString());
}
}
return s;
}

#endregion

#region 加入文字水印

/// summary>
/// 加入文字水印
/// /summary>
/// param name="fileName">文件名稱路徑(全路徑)/param>
/// param name="text">文件/param>
public void AddTextToImg(string fileName, string text)
{
if (!File.Exists(fileName))
{
throw new FileNotFoundException("文件不存在");
}
if (text == string.Empty)
{
return;
}

System.Drawing.Image image = System.Drawing.Image.FromFile(fileName);
Bitmap bitmap = new Bitmap(image, image.Width, image.Height);
Graphics g = Graphics.FromImage(bitmap);
float fontSize = 12.0f;//字體大小
float textWidth = text.Length * fontSize;//文本的長度
//下面定義一個矩形區域,以后在這個矩形里面畫上白底黑字
float rectX = 0;
float rectY = 0;
float rectWidth = text.Length * (fontSize + 8);
float rectHeight = fontSize + 8;
//聲明矩形域
RectangleF textArea = new RectangleF(rectX, rectY, rectWidth, rectHeight);
Font font = new Font("宋體", fontSize);//定義字體
Brush whiteBrush = new SolidBrush(Color.White);//白筆刷,畫文字用
Brush blackBrush = new SolidBrush(Color.Black);//黑筆刷，畫背景用
g.FillRectangle(blackBrush, rectX, rectY, rectWidth, rectHeight);
g.DrawString(text, font, whiteBrush, textArea);
MemoryStream ms = new MemoryStream();
bitmap.Save(ms, ImageFormat.Jpeg);
//輸出處理后的圖像，這里為了演示方便，我將圖片顯示在頁面中了
//Response.Clear();
//Response.ContentType = "image/jpeg";
//Response.BinaryWrite(ms.ToArray());
g.Dispose();
bitmap.Dispose();
image.Dispose();
}
#endregion
}
}

    System.Configuration.Configuration  
    config = WebConfigurationManager. 
    OpenWebConfiguration("~"); 
    HttpRuntimeSection section = config.GetSection 
    ("system.web/httpRuntime") as HttpRuntimeSection; 
    double maxFileSize = Math.Round 
    (section.MaxRequestLength / 1024.0, 1); 
    string errorString = string.Format("Make sure  
    your file is under {0:0.#} MB.", maxFileSize);

    protected override void OnError(EventArgs e) 
    { 
    HttpContext ctx = HttpContext.Current; 
    Exception exception = ctx.Server.GetLastError (); 

    string errorString =  
"
    Offending URL: " + ctx.Request.Url.ToString () + 
"
    Source: " + exception.Source +  
"
    Message: " + exception.Message + 
"
    Stack trace: " + exception.StackTrace; 

    ctx.Response.Write (errorString); 

    ctx.Server.ClearError (); 

    base.OnError (e); 
    }

IServiceProvider provider=(IServiceProvider) 
HttpContext.Current; 
HttpWorkerRequest wr=(HttpWorkerRequest) 
provider.GetService(typeof(HttpWorkerRequest)); 
byte[] bs=wr.GetPreloadedEntityBody(); 
if(!wr.IsEntireEntityBodyIsPreloaded()) 
{ 
int n=1024; 
byte[] bs2=new byte[n]; 
while(wr.ReadEntityBody(bs2,n) 〉0) 
{ 
} 
}