上传和下载

  1 <form id="form1" runat="server">
  2 <div>
  3 文件名：<asp:TextBox ID="TextBox1" runat="server"></asp:TextBox>
  4 <asp:Image ID="Image1" runat="server" />
  5 <asp:FileUpload ID="FileUpload1" runat="server" />
  6 <asp:Button ID="Button1" runat="server" Text="上传" OnClick="Button1_Click" />
  7 </div>
  8 </form>
  9 
 10  
 11 
 12 protected void Button2_Click(object sender, EventArgs e)
 13 {
 14 if (FileUpload1.HasFile)
 15 {
 16 HttpPostedFile hf = FileUpload1.PostedFile;
 17 string filename = hf.FileName;//全路径：F:asp456.jpg
 18 string fname = Path.GetFileName(filename);//文件名：456
 19 string ext = Path.GetExtension(fname).ToLower();//获取拓展名:.jpg
 20 Response.Write(fname + "<br/>" + ext);
 21 string[] exts = { ".jpg", ".jpeg", ".png", ".bmp", ".gif" };
 22 bool tag = false;
 23 foreach (string item in exts)
 24 {
 25 if (item == ext)
 26 {
 27 tag = true;
 28 break;
 29 }
 30 }
 31 if (tag)
 32 {
 33 if (hf.ContentLength < 1024 * 1024)
 34 {
 35 string uppath = "upload/";
 36 string dir = DateTime.Now.Year + "/" + DateTime.Now.Month + "/" + DateTime.Now.Day;
 37 string dirpath = Server.MapPath(uppath + dir);
 38 if (!Directory.Exists(dirpath))
 39 {
 40 Directory.CreateDirectory(dirpath);
 41 }
 42 if (TextBox1.Text != "")
 43 {
 44 fname = TextBox1.Text + ext;
 45 }
 46 hf.SaveAs(dirpath + fname);
 47 Image1.ImageUrl = uppath + dir + fname;
 48 Image1.Width = 400;
 49 Image1.Height = 300;
 50 }
 51 else
 52 {
 53 Response.Write("<script>alert('上传文件太大')</script>");
 54 }
 55 }
 56 }
 57 else
 58 {
 59 Response.Write("<script>alert('选择上传文件')</script>");
 60 }
 61 }
 62 
 63  
 64 
 65 
 66 ----------------------------------------------------------------------------------------------------------------------------------
 67 <form id="form1" runat="server">
 68 <div>Upload
 69 <asp:Image ID="Image1" runat="server" /></br>
 70 <span style="color:#4cff00" >图片预览</span></br>
 71 <asp:TextBox ID="txtCover" runat="server" ReadOnly="true"></asp:TextBox></br>
 72 <span style="color:#4cff00" >图片上传的路径</span></br>
 73 <asp:FileUpload ID="imgupload" runat="server" />&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;
 74 <asp:Button ID="btnUpload" runat="server" Text="上传" OnClick="btnUpload_Click" />
 75 
 76 </div>
 77 </form>
 78 
 79 protected void btnUpload_Click(object sender, EventArgs e)
 80 {
 81 #region
 82 //是否有文件加载
 83 if (imgupload.PostedFile.FileName != "")//不为空，证明有文件上传
 84 {
 85 //获取图片路径和文件名 imgPath=本地路径\本地二级路径\文件名.扩展名
 86 string imgPath = imgupload.PostedFile.FileName;//imgPath=D:ImageGroup$)91{Y9@Q(R@7@2M6APE_ZI.png
 87 //截取图片扩展名 +1？？？“1”是什么含义
 88 string extPath = imgPath.Substring(imgPath.LastIndexOf(".") + 1);//png jpg bmp
 89 //判断文件类型 为什么要用装换大小写？ToLower
 90 if (extPath.ToLower() != "bmp" && extPath.ToLower() != "jpg" && extPath.ToLower() != "png")
 91 {
 92 Page.ClientScript.RegisterClientScriptBlock(GetType(), "", "<script language=javascript>alert('选择文件类型JPG，bmp，PNG')</script>");
 93 
 94 }
 95 else
 96 {
 97 //思路：1.先定义好物理路径（文件 要保存到的文件夹）2.sPath+上传图片的xx+.jpg
 98 // 得到服务器的上传路径
 99 string sPath = Server.MapPath("/UploadFiles/upload");// MapPath物理路径就是右斜/
100 //保存到服务器 sPath＝UploadFilesupload
101 imgupload.PostedFile.SaveAs(sPath + @"" + imgPath.Substring(imgPath.LastIndexOf(@"") + 1));//存储虚拟路径+图片名字
102 sPath = sPath.Substring(sPath.LastIndexOf(@"") + 1); //sPath = 截取文件夹里的upload;
103 //在这里Spath被重置为upload
104 // 接下来就是要在TxtBox中显示路径
105 this.txtCover.Text = sPath + "/" + imgPath.Substring(imgPath.LastIndexOf(@"") + 1);//文件夹里的upload+xx.jpg;
106 // 这里txtCover的值为upload文件名.扩展名
107 Page.ClientScript.RegisterClientScriptBlock(GetType(), "", "<script language=javascript>alert('上传成功')</script>");
108 Image1.ImageUrl = "/UploadFiles/" + this.txtCover.Text;//?upload/$@B0)U`]TDA@MKRDW15BJQR.jpg
109 }
110 }
111 
112 else
113 {
114 Page.ClientScript.RegisterClientScriptBlock(GetType(), "", "<script language=javascript>alert('请选择图片')</script>");
115 }
116 #endregion