• node.js学习在页面上传图片并显示例子


    1、服务器启动js, index.js源码:

    var server = require("./server");
    var router = require("./router");
    var requestHandlers = require("./requestHandler");

    var handle = {};
    handle["/"] = requestHandlers.start;
    handle["/start"] = requestHandlers.start;
    handle["/upload"] = requestHandlers.upload;
    handle["/show"] = requestHandlers.show;

    server.start(router.route, handle);

    2、服务器server.js:

    var http= require("http");
    var url = require("url");
    function start(route, handle){
       function onRequest(request, response){
         var pathname = url.parse(request.url).pathname;
         console.log("Request for " + pathname + " received.");
         route(handle, pathname, response, request);
        
       }
      
       http.createServer(onRequest).listen(8888);
       console.log("Server has started.");

    }

    exports.start = start;

    3、路由选择route.js

    function route(handle,pathname,response, request){
     console.log("About to route a request for " + pathname);
     if(typeof handle[pathname] == 'function'){
       return handle[pathname](response, request);
     }else{
       console.log("No request handler found for " + pathname);
       //return "404 Not Found!";
       response.writeHead(404, {"Content-Type":"text/plain"});
       response.write("404 Not found");
       response.end();
     }
    }

    exports.route = route;

    4、请求处理程序requestHandler.js(使用node-formidable外部模块来处理文件上传,注意:要在index.js文件所在位置增加tmp文件夹,用于存放上传的图片)

    var exec = require("child_process").exec;
    var fs = require("fs");
    var formidable = require("formidable");
    function start(response, postData){
     console.log("Request handler 'start' was called.");
     var body = '<html>' +
            '<head>'  +
            '<meta http-equiv="Content-Type" content = "text/html;charset=UTF-8"/>' +
            '</head>' +
            '<body>' +
            '<form action="/upload" method="post" enctype="multipart/form-data" >' +
            '<textarea name="text" rows="20" cols="60"></textarea>' +
            '<textarea name="text2" rows="20" cols="60"></textarea>' +
            '<input type="file" name="upload" multiple="multiple">' +
            '<input type="submit" value="Upload File"/>' +
            '</form>' +
            '</body>' +
            '</html>';
      response.writeHead(200, {"Content-Type":"text/html"});
      response.write(body);
      response.end();
    }

    function upload(response, request){
     console.log("Request handler 'upload' was called");
     //return "Hello Upload";
     var form = new formidable.IncomingForm();
     form.uploadDir = "./tmp";
     console.log("about to parse");
     form.parse(request, function(error, fields, files){
      console.log("parsing done" + files.upload.path); 
      fs.renameSync(files.upload.path, "/tmp/test.png");
       response.writeHead(200, {"Content-Type":"text/html"});
       response.write('<head><meta charset="utf-8"/></head>');
       response.write("<img src='/show'/>");
       response.end();
     });
      
    }

    function show(response, postData){
     console.log("Request handler 'show' was called.");
     fs.readFile('/tmp/test.png', "binary", function(error, file){
          if(error){
            console.log("Request handler 'show' error:" + error);
            response.writeHead(500, {"Content-Type":"text/plain"});
            response.write(error + "\n");
            response.end();
          }else{
            response.writeHead(200, {"Content-Type":"image/png"});
            response.write(file, "binary");
            response.end();
          }
      });
    }

    exports.start = start;
    exports.upload = upload;
    exports.show = show;

    注:

     

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  • 原文地址:https://www.cnblogs.com/wangle1001986/p/3053502.html
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