前台页面:
<html xmlns="http://www.w3.org/1999/xhtml"> <head runat="server"> <title>简单图片上传示例</title> <script type="text/javascript"> </script> </head> <body> <form id="form1" runat="server"> <div> <asp:Label ID="Label1" runat="server" Text="Label"></asp:Label> <asp:FileUpload ID="FileUpload1" runat="server" /> <asp:Button ID="Button1" runat="server" OnClick="Button1_Click" Text="上传" /> <br /> <asp:Image ID="Image1" runat="server" /> </div> </form> </body> </html>
后台代码:
View Code
using System; using System.Collections.Generic; using System.Linq; using System.Web; using System.Web.UI; using System.Web.UI.WebControls; namespace 上传文件Demo { public partial class aspnet上传图片 : System.Web.UI.Page { protected void Page_Load(object sender, EventArgs e) { } protected void Button1_Click(object sender, EventArgs e) { try { if (FileUpload1.HasFile) { //文件名 string fileName = FileUpload1.FileName; //文件名(完全限定名:包含所在路径) //string filePath = FileUpload1.PostedFile.FileName; //文件类型 string fileType = FileUpload1.PostedFile.ContentType; string[] arrFileType = new string[]{ "image/jpeg", "image/jpeg", "image/jpeg", "image/bmp", "image/gif", "image/png" }; if (!arrFileType.Contains(fileType)) { Label1.Text = "请选择图片类型的文件!"; return; } //文件大小以字节为单位 int fileLength = FileUpload1.PostedFile.ContentLength; if (fileLength>1048576) { Label1.Text = "请选择小于1M的文件"; return; } //要在服务器上存储的名字 string newName = Guid.NewGuid().ToString(); //获取文件扩展名 string[] arr = fileName.Split('.'); string fType = newName + "." + arr[arr.Length - 1]; string serverPath = Server.MapPath("~/Images/") + fType; FileUpload1.SaveAs(serverPath); Image1.ImageUrl = "~/Images/" + fType; } else { Label1.Text = "请选择上传的文件"; } } catch (Exception ex) { Response.Write(ex.Message); } } } }
由于asp.net默认配置是限制了上传文件的大小为4M,超出时会报错.所以要自己做文件大小限定,要先修改web.config文件里
的上传文件大小限制,修改文件如下:
<?xml version="1.0"?> <!-- For more information on how to configure your ASP.NET application, please visit http://go.microsoft.com/fwlink/?LinkId=169433 --> <configuration> <system.web> <compilation debug="true" targetFramework="4.0" /> <!--修改上传文件的最大限制--> <httpRuntime maxRequestLength="40960" executionTimeout="3600" /> </system.web> </configuration>