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1 使用标准HTML来进行图片上传

前台代码:

<body> 
    
<form id="form1" runat="server"> 
    
<div> 
        
<table> 
            
<tr> 
                
<td colspan="2" style="height: 21px" > 
                    使用标准HTML来进行图片上传
</td> 
            
</tr> 
            
<tr> 
                
<td style="width: 400px"> 
                    
<input id="InputFile" style="width: 399px" type="file" runat="server" /></td> 
                
<td style="width: 80px"> 
                    
<asp:Button ID="UploadButton" runat="server" Text="上传图片" OnClick="UploadButton_Click" /></td> 
            
</tr> 
            
<tr> 
                
<td colspan="2" > 
                    
<asp:Label ID="Lb_Info" runat="server" ForeColor="Red"></asp:Label></td>                 
            
</tr> 
        
</table>     
    
</div> 
    
</form> 
</body>


后台代码:

 

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; 

public partial class _Default : System.Web.UI.Page  

    
protected void Page_Load(object sender, EventArgs e) 
    { 

    } 
    
protected void UploadButton_Click(object sender, EventArgs e) 
    { 
        
string uploadName = InputFile.Value;//获取待上传图片的完整路径,包括文件名 
        
//string uploadName = InputFile.PostedFile.FileName; 
        string pictureName = "";//上传后的图片名,以当前时间为文件名,确保文件名没有重复 
        if (InputFile.Value != ""
        { 
            
int idx = uploadName.LastIndexOf("."); 
            
string suffix = uploadName.Substring(idx);//获得上传的图片的后缀名 
            pictureName = DateTime.Now.Ticks.ToString() + suffix; 
        } 
        
try 
        { 
            
if (uploadName != ""
            { 
                
string path = Server.MapPath("~/images/"); 
                InputFile.PostedFile.SaveAs(path 
+ pictureName); 
            } 
        } 
        
catch (Exception ex) 
        { 
            Response.Write(ex); 
        } 
    } 
}


2 单文件上传

        这是最基本的文件上传,在asp.net1.x中没有这个FileUpload控件,只有html的上传控件,那时候要把html控件转化为服务器控件,很不好用。其实所有文件上传的美丽效果都是从这个FileUpload控件衍生,第一个例子虽然简单却是根本。

前台代码:

<body> 
    
<form id="form1" runat="server"> 
    
<div> 
        
<table style="width: 90%"> 
            
<tr> 
                
<td style="width: 159px" colspan=2> 
                    
<strong><span style="font-size: 10pt">最简单的单文件上传</span></strong></td> 
            
</tr> 
            
<tr> 
                
<td style="width: 600px"> 
                    
<asp:FileUpload ID="FileUpload1" runat="server" Width="600px" /></td> 
                
<td align=left> 
                    
<asp:Button ID="FileUpload_Button" runat="server" Text="上传图片" OnClick="FileUpload_Button_Click" /></td> 
            
</tr> 
            
<tr> 
                
<td colspan=2> 
                    
<asp:Label ID="Upload_info" runat="server" ForeColor="Red" Width="767px"></asp:Label></td> 
            
</tr> 
        
</table>     
    
</div> 
    
</form> 
</body>

后台代码:

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; 

public partial class _Default : System.Web.UI.Page  

    
protected void Page_Load(object sender, EventArgs e) 
    { 

    } 
    
protected void FileUpload_Button_Click(object sender, EventArgs e) 
    { 
        
try 
        { 
            
if (FileUpload1.PostedFile.FileName == ""
            
//if (FileUpload1.FileName == "") 
            
//if (!FileUpload1.HasFile)     //获取一个值,该值指示 System.Web.UI.WebControls.FileUpload 控件是否包含文件。包含文件,则为 true;否则为 false。 
            { 
                
this.Upload_info.Text = "请选择上传文件!"
            } 
            
else 
            { 
                
string filepath = FileUpload1.PostedFile.FileName;  //得到的是文件的完整路径,包括文件名,如:C:\Documents and Settings\Administrator\My Documents\My Pictures\20022775_m.jpg 
                
//string filepath = FileUpload1.FileName;               //得到上传的文件名20022775_m.jpg 
                string filename = filepath.Substring(filepath.LastIndexOf("\\"+ 1);//20022775_m.jpg 
                string serverpath = Server.MapPath("~/images/"+ filename;//取得文件在服务器上保存的位置C:\Inetpub\wwwroot\WebSite1\images\20022775_m.jpg 
                FileUpload1.PostedFile.SaveAs(serverpath);//将上传的文件另存为 
                this.Upload_info.Text = "上传成功!"
            } 
        } 
        
catch (Exception ex) 
        { 
            
this.Upload_info.Text = "上传发生错误!原因是:" + ex.ToString(); 
        } 
    } 
}




 3 多文件上传

前台代码:

<body> 
    
<form id="form1" runat="server"> 
    
<div> 
    
<table style="width: 343px"> 
            
<tr> 
                
<td style="width: 100px"> 
                    多文件上传
</td> 
                
<td style="width: 100px"> 
                
</td> 
            
</tr> 
            
<tr> 
                
<td style="width: 100px"> 
                    
<asp:FileUpload ID="FileUpload1" runat="server" Width="475px" /> 
                    
</td> 
                
<td style="width: 100px"> 
                    
</td> 
            
</tr> 
            
<tr> 
                
<td style="width: 100px"> 
                    
<asp:FileUpload ID="FileUpload2" runat="server" Width="475px" /></td> 
                
<td style="width: 100px"> 
                
</td> 
            
</tr> 
            
<tr> 
                
<td style="width: 100px"> 
                    
<asp:FileUpload ID="FileUpload3" runat="server" Width="475px" /></td> 
                
<td style="width: 100px"> 
                
</td> 
            
</tr> 
            
<tr> 
                
<td style="width: 100px"> 
                    
<asp:Button ID="bt_upload" runat="server" OnClick="bt_upload_Click" Text="一起上传" /> 
                    
<asp:Label ID="lb_info" runat="server" ForeColor="Red" Width="448px"></asp:Label></td> 
                
<td style="width: 100px"> 
                
</td> 
            
</tr> 
        
</table> 
    
</div> 
    
</form> 
</body>

 后台代码:

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; 

public partial class _Default : System.Web.UI.Page  

    
protected void Page_Load(object sender, EventArgs e) 
    { 

    } 
    
protected void bt_upload_Click(object sender, EventArgs e) 
    { 
        
if (FileUpload1.PostedFile.FileName == "" && FileUpload2.PostedFile.FileName == "" && FileUpload3.PostedFile.FileName == ""
        { 
            
this.lb_info.Text = "请选择文件!"
        } 
        
else 
        { 
            HttpFileCollection myfiles 
= Request.Files; 
            
for (int i = 0; i < myfiles.Count; i++
            { 
                HttpPostedFile mypost 
= myfiles[i]; 
                
try 
                { 
                    
if (mypost.ContentLength > 0
                    { 
                        
string filepath = mypost.FileName;//C:\Documents and Settings\Administrator\My Documents\My Pictures\20022775_m.jpg 
                        string filename = filepath.Substring(filepath.LastIndexOf("\\"+ 1);//20022775_m.jpg 
                        string serverpath = Server.MapPath("~/images/"+ filename;//C:\Inetpub\wwwroot\WebSite2\images\20022775_m.jpg 
                        mypost.SaveAs(serverpath); 
                        
this.lb_info.Text = "上传成功!"
                    } 
                } 
                
catch (Exception ex) 
                { 
                    
this.lb_info.Text = "上传发生错误!原因:" + ex.Message.ToString(); 
                } 
            } 
        } 
    } 
}


  

4 客户端检查上传文件类型(以上传图片为例)

 

<%@ Page Language="C#" AutoEventWireup="true"  CodeFile="Default.aspx.cs" Inherits="_Default" %> 

<!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"> 
    
<title>客户端检查上传文件类型</title> 
    
<script language="javascript"> 
    
function Check_FileType() 
    { 
        
var str=document.getElementById("FileUpload1").value; 
        
var pos=str.lastIndexOf("."); 
        
var lastname=str.substring(pos,str.length); 
        
if(lastname.toLowerCase()!=".jpg"&&lastname.toLowerCase()!=".gif"
        { 
            alert(
"您上传的文件类型为"+lastname+",图片必须为.jpg,.gif类型"); 
            
return false
        } 
        
else 
        { 
            
return true
        }         
    } 
    
</script> 
</head> 
<body> 
    
<form id="form1" runat="server"> 
    
<div> 
        
<table> 
            
<tr> 
                
<td colspan="2"> 
                    客户端检查上传文件类型
</td>                 
            
</tr> 
            
<tr> 
                
<td style="width: 444px"> 
                    
<asp:FileUpload ID="FileUpload1" runat="server" Width="432px" /></td> 
                
<td style="width: 80px"> 
                    
<asp:Button ID="bt_upload" runat="server" Text="上传图片" OnClick="bt_upload_Click" OnClientClick="return Check_FileType()" /></td> 
            
</tr> 
            
<tr> 
                
<td colspan="2" style="height: 21px"> 
                    
<asp:Label ID="lb_info" runat="server" ForeColor="Red" Width="515px"></asp:Label></td>                 
            
</tr> 
        
</table>     
    
</div> 
    
</form> 
</body> 
</html>


注意:点击上传时先触发客户端事件OnClientClick="return Check_FileType()"

 

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; 

public partial class _Default : System.Web.UI.Page  

    
protected void Page_Load(object sender, EventArgs e) 
    { 

    } 

    
protected void bt_upload_Click(object sender, EventArgs e) 
    { 
        
try 
        { 
            
if (FileUpload1.PostedFile.FileName == ""
            { 
                
this.lb_info.Text = "请选择文件!"
            } 
            
else 
            { 
                
string filepath = FileUpload1.PostedFile.FileName; 
                
//if (!IsAllowedExtension(FileUpload1)) 
                
//
                
//    this.lb_info.Text = "上传文件格式不正确!"; 
                
//
                if (IsAllowedExtension(FileUpload1) == true
                { 
                    
string filename = filepath.Substring(filepath.LastIndexOf("\\"+ 1); 
                    
string serverpath = Server.MapPath("~/images/"+ filename; 
                    FileUpload1.PostedFile.SaveAs(serverpath); 
                    
this.lb_info.Text = "上传成功!"
                } 
                
else 
                { 
                    
this.lb_info.Text = "请上传图片!"
                } 
            } 
        } 
        
catch (Exception ex) 
        { 
            
this.lb_info.Text = "上传发生错误!原因:" + ex.ToString(); 
        } 
    } 
    
private static bool IsAllowedExtension(FileUpload upfile) 
    { 
        
string strOldFilePath = ""
        
string strExtension=""
        
string[] arrExtension =".gif"".jpg"".bmp"".png" }; 
        
if (upfile.PostedFile.FileName != string.Empty) 
        { 
            strOldFilePath 
= upfile.PostedFile.FileName;//获得文件的完整路径名 
            strExtension = strOldFilePath.Substring(strOldFilePath.LastIndexOf("."));//获得文件的扩展名,如:.jpg 
            for (int i = 0; i < arrExtension.Length; i++
            { 
                
if (strExtension.Equals(arrExtension[i])) 
                { 
                    
return true
                } 
            } 
        } 
        
return false
    } 
}


注意:若去掉客户端的脚本和客户端事件OnClientClick="return Check_FileType()",在后台代码
改为:

if (!IsAllowedExtension(FileUpload1)) 
                { 
                    
this.lb_info.Text = "上传文件格式不正确!"
                } 
else if (IsAllowedExtension(FileUpload1) == true)


即变成服务器端检查上传文件类型。

5  服务器端检查上传文件的类型(文件内部真正的格式)

<body> 
    
<form id="form1" runat="server"> 
    
<div> 
        
<table> 
            
<tr> 
                
<td colspan="2"> 
                    服务器检查上传文件类型
</td>                 
            
</tr> 
            
<tr> 
                
<td style="width: 444px"> 
                    
<asp:FileUpload ID="FileUpload1" runat="server" Width="432px" /></td> 
                
<td style="width: 80px"> 
                    
<asp:Button ID="bt_upload" runat="server" Text="上传图片" OnClick="bt_upload_Click" /></td> 
            
</tr> 
            
<tr> 
                
<td colspan="2" style="height: 21px"> 
                    
<asp:Label ID="lb_info" runat="server" ForeColor="Red" Width="515px"></asp:Label></td>                 
            
</tr> 
        
</table>     
    
</div> 
    
</form> 
</body>

 

后台代码:

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.IO; 

public partial class _Default : System.Web.UI.Page  

    
protected void Page_Load(object sender, EventArgs e) 
    { 

    } 
    
protected void bt_upload_Click(object sender, EventArgs e) 
    { 
        
try 
        { 
            
if (FileUpload1.PostedFile.FileName == ""
            { 
                
this.lb_info.Text = "请选择文件!"
            } 
            
else 
            { 
                
string filepath = FileUpload1.PostedFile.FileName; 
                
if (IsAllowedExtension(FileUpload1) == true
                { 
                    
string filename = filepath.Substring(filepath.LastIndexOf("\\"+ 1); 
                    
string serverpath = Server.MapPath("images/"+ filename; 
                    FileUpload1.PostedFile.SaveAs(serverpath); 
                    
this.lb_info.Text = "上传成功!"
                } 
                
else 
                { 
                    
this.lb_info.Text = "请上传图片"
                } 
            } 
        } 
        
catch (Exception error) 
        { 
            
this.lb_info.Text = "上传发生错误!原因:" + error.ToString(); 
        } 
    } 
    
private static bool IsAllowedExtension(FileUpload upfile) 
    { 
        FileStream fs 
= new FileStream(upfile.PostedFile.FileName, FileMode.Open, FileAccess.Read); 
        BinaryReader r 
= new BinaryReader(fs); 
        
string fileclass = ""
        
byte buffer; 
        
try 
        { 
            buffer 
= r.ReadByte(); 
            fileclass 
= buffer.ToString(); 
            buffer 
= r.ReadByte(); 
            fileclass 
+= buffer.ToString(); 
        } 
        
catch 
        {  
             
        } 
        r.Close(); 
        fs.Close(); 
        
if (fileclass == "255216" || fileclass == "7173"||fileclass=="6677"||fileclass=="13780")//说明255216是jpg;7173是gif;6677是BMP,13780是PNG;7790是exe,8297是rar 
        { 
            
return true
        } 
        
else 
        { 
            
return false
        } 
    } 
}

 

转自: http://blog.csdn.net/qing0991/archive/2008/09/06/2890654.aspx

 

posted on 2009-08-21 10:29 钱途无梁 阅读(...) 评论(...) 编辑 收藏