由于需要圖片上傳的功能，所以花了一些時間網上找相關資料終于搞定，效果圖如下：
下面的是解決方案截圖和上傳的圖片截圖：
具體實現代碼如下：
1.界面代碼
<%@ Page Language="C#" AutoEventWireup="true" CodeBehind="UploadPic.aspx.cs" Inherits="Pic_Try.UploadPic" %><!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>圖片上傳和顯示</title> <style type="text/css"> .pic_text{ color:Red;} .pic_label { color:Gray; margin-top:5px; margin-bottom:5px;} .pic_image { margin:5px;} </style></head><body> <form id="form1" runat="server"> <div class="pic_image"><asp:Image ID="pic" runat="server" /></div> <div><asp:FileUpload ID="pic_upload" runat="server" /><asp:Label ID="lbl_pic" runat="server" class="pic_text"></asp:Label></div> <div class="pic_label">上傳圖片格式為.jpg, .gif, .bmp,.png,圖片大小不得超過8M</div> <div><asp:Button ID="btn_upload" runat="server" Text="上傳" onclick="btn_upload_Click"/></div> </form> </body></html>2.后臺代碼UploadPic.aspx.cs
using System;using System.Collections.Generic;using System.Linq;using System.Web;using System.Web.UI;using System.Web.UI.WebControls;using System.IO;using System.Security.Cryptography;using System.Web.Security;namespace Pic_Try{ public partial class UploadPic : System.Web.UI.Page { protected void Page_Load(object sender, EventArgs e) { } protected void btn_upload_Click(object sender, EventArgs e) { Boolean fileOk = false; if (pic_upload.HasFile)//驗證是否包含文件 { //取得文件的擴展名,并轉換成小寫 string fileExtension = Path.GetExtension(pic_upload.FileName).ToLower(); //驗證上傳文件是否圖片格式 fileOk = IsImage(fileExtension); if (fileOk) { //對上傳文件的大小進行檢測，限定文件最大不超過8M if (pic_upload.PostedFile.ContentLength < 8192000) { string filepath = "/images/"; if (Directory.Exists(Server.MapPath(filepath)) == false)//如果不存在就創建file文件夾 { Directory.CreateDirectory(Server.MapPath(filepath)); } string virpath = filepath + CreatePasswordHash(pic_upload.FileName, 4) + fileExtension;//這是存到服務器上的虛擬路徑 string mappath = Server.MapPath(virpath);//轉換成服務器上的物理路徑 pic_upload.PostedFile.SaveAs(mappath);//保存圖片 //顯示圖片 pic.ImageUrl = virpath; //清空提示 lbl_pic.Text = ""; } else { pic.ImageUrl = ""; lbl_pic.Text = "文件大小超出8M！請重新選擇！"; } } else { pic.ImageUrl = ""; lbl_pic.Text = "要上傳的文件類型不對！請重新選擇！"; } } else { pic.ImageUrl = ""; lbl_pic.Text = "請選擇要上傳的圖片！"; } } /// <summary> /// 驗證是否指定的圖片格式 /// </summary> /// <param name="str"></param> /// <returns></returns> public bool IsImage(string str) { bool isimage = false; string thestr = str.ToLower(); //限定只能上傳jpg和gif圖片 string[] allowExtension = { ".jpg", ".gif", ".bmp",".png" }; //對上傳的文件的類型進行一個個匹對 for (int i = 0; i < allowExtension.Length; i++) { if (thestr == allowExtension[i]) { isimage = true; break; } } return isimage; } /// <summary> /// 創建一個指定長度的隨機salt值 /// </summary> public string CreateSalt(int saltLenght) { //生成一個加密的隨機數 RNGCryptoServiceProvider rng = new RNGCryptoServiceProvider(); byte[] buff = new byte[saltLenght]; rng.GetBytes(buff); //返回一個Base64隨機數的字符串 return Convert.ToBase64String(buff); } /// <summary> /// 返回加密后的字符串 /// </summary> public string CreatePasswordHash(string pwd, int saltLenght) { string strSalt = CreateSalt(saltLenght); //把密碼和Salt連起來 string saltAndPwd = String.Concat(pwd, strSalt); //對密碼進行哈希 string hashenPwd = FormsAuthentication.HashPasswordForStoringInConfigFile(saltAndPwd, "sha1"); //轉為小寫字符并截取前16個字符串 hashenPwd = hashenPwd.ToLower().Substring(0, 16); //返回哈希后的值 return hashenPwd; } }}3.最后防止上傳大文件圖片時報錯，配置文件添加配置Web.config
<?xml version="1.0" encoding="utf-8"?><!-- 有關如何配置 ASP.NET 應用程序的詳細消息，請訪問 http://go.microsoft.com/fwlink/?LinkId=169433 --><configuration> <system.web> <compilation debug="true" targetFramework="4.0" /> <httpRuntime executionTimeout="240" maxRequestLength="8192000"/> </system.web></configuration>
以上就是本文的全部內容，希望對大家的學習有所幫助，也希望大家多多支持武林網。
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