asp.net 上传图片并同时生成缩略图的代码

代码如下:

<%@ Page Language="C#" ResponseEncoding="gb2312" %>
<%@ Import Namespace="System" %>
<%@ Import Namespace="System.IO" %>
<%@ Import Namespace="System.Drawing" %>
<%@ Import Namespace="System.Drawing.Imaging" %>
<script runat="server">
　
void Page_Load(Object sender, EventArgs e)
{
if (!Page.IsPostBack)
{
ImgPreview.Visible = false;
}
}
void GetThumbnailImage(int width, int height, string strInfo, int left, int right)
{
string file = "Uploads/" + uploadFile.PostedFile.FileName.Substring(uploadFile.PostedFile.FileName.LastIndexOf('\\') + 1);
string newfile = "Uploads/" + uploadFile.PostedFile.FileName.Substring(uploadFile.PostedFile.FileName.LastIndexOf('\\') + 1) + ".jpg";
string strAdd = strInfo;
System.Drawing.Image oldimage = System.Drawing.Image.FromFile(Server.MapPath(file));
System.Drawing.Image thumbnailImage =
oldimage.GetThumbnailImage(width, height, new System.Drawing.Image.GetThumbnailImageAbort(ThumbnailCallback), IntPtr.Zero);
Response.Clear();
Bitmap output = new Bitmap(thumbnailImage);
Graphics g = Graphics.FromImage(output);
g.DrawString(strAdd, new Font("Courier New", 14), new SolidBrush(Color.Red), left, right);
output.Save(Server.MapPath(newfile), System.Drawing.Imaging.ImageFormat.Jpeg);
Response.ContentType = "image/gif";
ImgPreview.Visible = true;
ImgPreview.ImageUrl = newfile;
}
bool ThumbnailCallback()
{
return true;
}
void Button_Click(object sender, EventArgs e)
{
int width, height, left, right;
string strAddInfo = txtAddInfo.Text;
width = Int32.Parse(txtWidth.Text);
height = Int32.Parse(txtHeight.Text);
left = Int32.Parse(txtLeft.Text);
right = Int32.Parse(txtRight.Text);
if (!(uploadFile.PostedFile.ContentLength > 0))
{
lblErrInfo.Text = "没有选择文件";
}
else
{
string path = Server.MapPath("./Uploads/" + uploadFile.PostedFile.FileName.Substring(uploadFile.PostedFile.FileName.LastIndexOf('\\') + 1));
if (File.Exists(path))
{
lblErrInfo.Text = "已经有同名文件";
}
else
{
uploadFile.PostedFile.SaveAs(path);
GetThumbnailImage(width, height, strAddInfo, left, right);
}
}
}
</script>
<html xmlns="http://www.w3.org/1999/xhtml">
<head id="Head1" runat="server">
<title>上传图片并生成缩略图</title>
</head>
<body>
<form id="Form1" method="post" enctype="multipart/form-data" runat="server">
<p>
<input id="uploadFile" type="file" runat="server" />
<asp:Label ID="lblErrInfo" runat="server" ForeColor="Red"></asp:Label>
</p>
<p>
width:<asp:TextBox ID="txtWidth" runat="server" Width="40px">100</asp:TextBox>
height:<asp:TextBox ID="txtHeight" runat="server" Width="40px">150</asp:TextBox>
</p>
<p>
添加信息：<asp:TextBox ID="txtAddInfo" runat="server"> AspxBoy.Com</asp:TextBox>
</p>
<p>
信息位置：left:<asp:TextBox ID="txtLeft" runat="server" Width="40px">10</asp:TextBox>
right:<asp:TextBox ID="txtRight" runat="server" Width="40px">135</asp:TextBox>
</p>
<p>
<input id="button" type="button" value="上传生成所略图" onserverclick="Button_Click" runat="server" />
</p>
<p>
<asp:Image ID="ImgPreview" runat="server"></asp:Image>
</p>
<!-- Insert content here -->
</form>
</body>
</html>

asp.net(vbscript)上传图片并同时生成缩略图：


代码如下:

　　<script language="VB" runat="server">
　　Sub UploadFile(sender As Object, e As EventArgs)
　　If FileUp.PostedFile.ContentLength = 0 Then
　　FileInfo.Visible = False
　　Exit Sub
　　Else
　　FileInfo.Visible = True
　　FDisplay1.Visible = True
　　End If
　　FSize.Text ="上传文件大小"+ CStr(FileUp.PostedFile.ContentLength/1024)+"KB"
　　FName.Text = "已上传文件名:"+FileUp.PostedFile.FileName+"<br>"+FName.Text
　　"写入数据库
　　on error resume next
　　dim myconn as sqlconnection
　　dim mycomm as sqlcommand
　　dim sql as string
　　dim id as integer
　　Dim image,anewimage As System.Drawing.Image
　　dim width,height,newwidth,newheight as integer
　　Dim callb As System.Drawing.Image.GetThumbnailImageAbort
　　myConn=New sqlconnection(ConfigurationSettings.AppSettings("数据库"))
　　myconn.open()
　　sql="insert into picture (姓名,班级,介绍,属性) values (""&request.cookies("dgxyl").values("dgxylname")&"",""&request.cookies("dgxyl").values("dgxylbj")&"",""&trim(request("TextBox1"))&"",""&request("r1")&"")"
　　Mycomm=New sqlcommand(sql,myconn)
　　mycomm.executenonquery()
　　myconn.close()
　　Dim myCommand As New SqlCommand("select top 1 id from picture order by id desc", myConn)
　　myCommand.Connection.Open()
　　Dim myReader As SqlDataReader=mycommand.executereader()
　　if myReader.Read() then
　　id=myReader("id")
　　end if
　　myconn.close()
　　"保存图片
　　FileUp.PostedFile.SaveAs( Server.MapPath("\classpic\")&cstr(id)&".jpg" )
　　"生成缩略图
　　image=System.Drawing.Image.FromFile(Server.MapPath("/classpic/"+cstr(id)+".jpg"))
　　width=image.Width
　　height=image.height
　　if width>height then
　　newwidth=250
　　newheight=image.height/image.Width*newwidth
　　else
　　newheight=250
　　newwidth=image.Width/image.height*newheight
　　end if
　　response.write("id="+cstr(id)+"width="+cstr(Width)+";height="+cstr(height)+" ")
　　response.write("newwidth="+cstr(newwidth)+";newheight="+cstr(newheight)+"<br>")
　　aNewImage=image.GetThumbnailImage(newwidth,newheight,callb,new System.IntPtr())
　　aNewImage.Save(Server.MapPath("/smallpic/"+cstr(id)+".jpg"))
　　image.Dispose()
　　Dim FileSplit() As String = Split( FileUp.PostedFile.FileName, "\" )
　　Dim FileName As String = FileSplit(FileSplit.Length-1)
　　Dim Exts() As String = Split( FileName, "." )
　　Dim Ext As String = LCase(Exts(Exts.Length-1))
　　FDisplay.Text = "<A Target="_blank" HREF="/classpic/"&cstr(id)&".jpg"& "">查看上传文件</A>"
　　FDisplay1.text="<a href="/picture/default.asp?bj="&cstr(request.cookies("dgxyl").values("dgxylbj"))&"">返回</a>"
　　End Sub
　　</script>
　　<SCRIPT language=JavaScript>
　　<!--
　　var requestsubmitted=false;
　　function guestbook_Validator(theForm)
　　{
　　//检查是否从新提交
　　if (requestsubmitted==true){
　　alert("你已经提交了留言，请等待服务器应答！");
　　return(false);
　　}
　　requestsubmitted=true;
　　return (true);
　　}
　　//-->
　　</SCRIPT>
<Html>
　　<Body BgColor=White>
　　<H3 align="center">请正确填写下面各项</h3>
　　<Hr></H3>
　　<Div id="FileInfo" Visible="False" runat="server">
　　<Asp:Label id="FSize" runat="server"/><br>
　　<Asp:Label id="FName" runat="server"/><br>
　　<Asp:Label id="FDisplay" runat="server"/>
　　<Asp:Label id="FDisplay1" runat="server"/>
　　</Div>
　　<Form Enctype="multipart/form-data" onsubmit="return guestbook_Validator(this)" runat="server">
　　上传文件
　　<Input Type="File" id="FileUp" runat="server" size="20"><br>
　　图片属性：<input type="radio" value="<%=request.cookies("dgxyl").values("dgxylbj")%>" name="R1" checked>本班<input type="radio" value="全　　校" name="R1">全校(本班则只在本班显示，全校则在全校显示)<P>
　　图片说明：<br>
　　<asp:TextBox id="TextBox1" runat="server" Width="233px" Height="141px">
　　</asp:TextBox>
　　<asp:RequiredFieldValidator id="RequiredFieldValidator1" runat="server" ControlToValidate="TextBox1" ErrorMessage="请输入图片说明">
　　</asp:RequiredFieldValidator><br>
　　<Asp:button id="Upload" OnClick="UploadFile" Text="上传图片" runat="server"/>
　　</form>
　　<Hr>
　　<p>注意：</p>
　　<ol>
　　<li><b>严禁上传污染环境的照片，否则账号将被删除！</b></li>
　　<li><font color="#808000"><b>请详细填写照片说明，图片说明不详细将会被视为乱传图片，将会被删除！</b></font></li>
　　</ol>
　　</Body>
　　</Html>