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  • 普通文件的上传(表单上传和ajax文件异步上传)

    一、表单上传:

    html客户端部分:

    <form action="upload.ashx" method="post" enctype="multipart/form-data">
            选择文件:<input type="file" name="file1" /><br />
            <input type="submit" value="上传" />
    </form>
    一般处理程序服务器端:
    public void ProcessRequest(HttpContext context)
            {
                context.Response.ContentType = "text/plain";
                HttpPostedFile file1 = context.Request.Files["file1"];
                helper.uploadFile(file1, "~/upload/");//这里就是对相应方法进行调用
                context.Response.Write("ok");//提示执行成功
            }
    上传代码的封装:
    /// <summary>
            /// 上传图片
            /// </summary>
            /// <param name="file">通过form表达提交的文件</param>
            /// <param name="virpath">文件要保存的虚拟路径</param>
            public static void uploadImg(HttpPostedFile file,string virpath)
            {          
                if (file.ContentLength > 1024 * 1024 * 4)
                {
                    throw new Exception("文件不能大于4M");
                }
                string imgtype = Path.GetExtension(file.FileName);
                if(imgtype!=".jpg"&&imgtype!=".jpeg")  //图片类型进行限制
                {
                    throw new Exception("请上传jpg或JPEG图片");
                }
                using (Image img = Bitmap.FromStream(file.InputStream))
                {
                    string savepath = HttpContext.Current.Server.MapPath(virpath+file.FileName);
                    img.Save(savepath);
                }
            }
            /// <summary>
            /// 上传文件
            /// </summary>
            /// <param name="file">通过form表达提交的文件</param>
            /// <param name="virpath">文件要保存的虚拟路径</param>
            public static void uploadFile(HttpPostedFile file, string virpath)
            {
                if (file.ContentLength > 1024 * 1024 * 6)
                {
                    throw new Exception("文件不能大于6M");
                }
                string imgtype = Path.GetExtension(file.FileName);
                //imgtype对上传的文件进行限制
                if (imgtype != ".zip" && imgtype != ".mp3")
                {
                    throw new Exception("只允许上传zip、rar....文件");
                }
                string dirFullPath=  HttpContext.Current.Server.MapPath(virpath);
                if (!Directory.Exists(dirFullPath))//如果文件夹不存在,则先创建文件夹
                {
                    Directory.CreateDirectory(dirFullPath);
                }
                file.SaveAs(dirFullPath + file.FileName);
            }

    二、Ajax文件异步上传:

    注明:既然有了表单上传为什么又要ajax上传呢?因为表单上传过程中,整个页面就刷新了!ajax异步上传就可以达到只刷新局部位置,下面就简单看看ajax上传吧!

    html客户端部分:

    <html lang="en">
    
    <head>
        <meta charset="UTF-8">
        <meta name="viewport" content="width=device-width, initial-scale=1.0">
        <meta http-equiv="X-UA-Compatible" content="ie=edge">
        <title>Document</title>
    </head>
    
    <body>
        <h2>文件上传</h2>
        <form action="/api/upload" method="post" enctype="multipart/form-data">
            <input type="file" id="file1" /><br />
            <input type="button" value="submit" id="submit-button" />
        </form>
    </body>
    <script src="/static/libs/jquery/jquery-1.11.2.min.js"></script>
    <script>
        $("#submit-button").click(function (e) {
            e.preventDefault();
            
            var formData = new FormData();
            formData.append("pic-upload", document.getElementById("file1").files[0]);
    
            $.ajax({
                type: 'POST',
                url: "/api/upload",
                data: formData,
                //必须false才会自动加上正确的Content-Type
                contentType: false,
                // 必须false才会避开jQuery对 formdata 的默认处理,XMLHttpRequest会对 formdata 进行正确的处理
                processData: false,
                success: function (response) {
                    console.log(response);
                },
                error: function (response) {
                    console.log(response);
                }
            });
        })
    </script>
    
    </html>
    node.js服务器端:
    const express = require("express")
    const fs = require("fs")
    const mysql = require("mysql")
    const util = require("util")
    const { getNow } = require("./tool")
    
    const app = express();
    
    var multer = require('multer');//获得中间件
    var upload = multer({dest:'uploads/'});//指定配置项,这里指定文件保存于当前目录下的upload子目录
    app.use(upload.single('pic-upload'));//运用中间件,并且指明文件名,此名需要同html input name的文件名一致,否则会报错
    
    const bodyParser = require("body-parser");
    const { nextTick } = require("process");
    app.use("/static/", express.static("./static/"));
    app.use('/node_modules/', express.static('./node_modules/'));
    app.engine("html", require("express-art-template"))
    app.use(bodyParser.urlencoded({ extended: false }))
    app.use(bodyParser.json())
    
    app.get("/upload", (req, res) => {
        res.render("upload.html");
    })
    
    app.post("/api/upload", (req, res) => {
        // 没有附带文件
        res.send(req.file);    //服务端响应把客户端获得的文件信息显示在客户端
    })
    
    
    app.get("/404", (req, res) => {
        res.render("404.html");
    })
    
    // 配置一个全局错误处理中间件
    app.use(function (err, req, res, next) {
        res.status(500).json({
            err_code: 500,
            message: err.message
        })
    })
    
    app.listen(5555, () => {
        console.log("服务启动成功......");
    })
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  • 原文地址:https://www.cnblogs.com/samve/p/14274755.html
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