<input type="file" id=m onpropertychange="document.all.a.src=this.value;alert(document.all.a.width+':'+document.all.a.height)">
<img id=a style="visibility:hidden">

解决方案 »

  1.   

    上传时图片可以改大小,图上写字
     hp.q 发表于 2000-11-23 16:28:36 .NET技术 ←返回版面         [快速返回] <%@ Page Language="c#" Debug="true" Trace="true"%>
    <%@ Import Namespace="System.IO" %>
    <%@ Import Namespace="System.Drawing" %>
    <%@ Import Namespace="System.Drawing.Imaging" %>
    <html>
    <script runat =server>
          void UploadBtn_Click(Object sender, EventArgs e) {
             String filename;
             String filename1;
             String[] filename2;
             int q;
             filename=UploadFile.PostedFile.FileName ;
             filename2=filename.Split(new Char[] {'\\'});
             q=filename2.GetUpperBound(0);
             filename1=filename2[q];
             dis.Text="上传文件名:"+filename1+"<br>";
             UploadFile.PostedFile.SaveAs(Server.MapPath(filename1));
             ImageEditor.Visible = true;
             dis.Text+="文件大小:"+UploadFile.PostedFile.ContentLength+"字节数";
             Image1.Src=filename1;      
          } 
          void UpdateBtn_Click(Object sender, EventArgs e) {
             String filename1;
             filename1=Image1.Src;
             System.Drawing.Image image = System.Drawing.Image.FromFile(Server.MapPath(filename1));
             System.Drawing.Image newimage = new Bitmap(image.Width, image.Height, PixelFormat.Format32bppRGB);
             Graphics g = Graphics.FromImage(newimage);
             g.DrawImage(image,0,0,image.Width,image.Height);
             Font f = new Font(FontType.SelectedItem.Text, Int32.Parse(FontSize.SelectedItem.Text));
             Brush b = new SolidBrush(Color.Red);
             g.DrawString(Caption.Text, f, b, 10, 140);
             g.Dispose();
             System.Drawing.Image thumbImage = newimage.GetThumbnailImage(Int32.Parse(Width.Text),Int32.Parse(Height.Text),null,0);
             image.Dispose();
             thumbImage.Save(Server.MapPath(filename1), ImageFormat.JPEG);
             Image1.Src=filename1;       
             Caption.Text="";     
       
          }   </script>   <body>
       <asp:label id="dis" runat=server/>
         <form enctype="multipart/form-data" runat=server>          <h3>          Select File To Upload: <input id="UploadFile" type=file runat=server>          <asp:button Text="Upload Me!" OnClick="UploadBtn_Click" runat=server/>          <hr>
          
              <asp:panel id="ImageEditor" Visible=false runat=server>             <img ID="Image1" src="" runat="server"/>             <h3>
                    Image Width: <asp:textbox id="Width" runat=server/>                 Image Height: <asp:textbox id="Height" runat=server/> <br>                 Text Caption: <asp:textbox id="Caption" runat=server/>                 Caption Size: <asp:dropdownlist id="FontSize" runat=server>
                                             <asp:listitem>14</asp:listitem>
                                             <asp:listitem>18</asp:listitem>
                                             <asp:listitem>26</asp:listitem>
                                             <asp:listitem>36</asp:listitem>
                                             <asp:listitem>48</asp:listitem>
                                             <asp:listitem>62</asp:listitem>
                                          </asp:dropdownlist>
                     Caption Font: <asp:dropdownlist id="FontType" runat=server>
                                             <asp:listitem>黑体</asp:listitem>
                                             <asp:listitem>仿宋</asp:listitem>
                                             <asp:listitem>隶书</asp:listitem>
                                             <asp:listitem>楷书</asp:listitem>
                                             <asp:listitem>方正姚体</asp:listitem>
                                             <asp:listitem>华文彩云</asp:listitem>
                                          </asp:dropdownlist>
                                                    
                     <asp:button Text="Update Image" OnClick="UpdateBtn_Click" runat=server/>             </h3> 
              </asp:panel>      </form>   </body>
    </html> 
     
      

  2.   

    那么,有什么办法可以在上传之前就判断用户上传的图片是否在我设置的范围内,如height在100-150之间,width在100-200之间呢?