node接收blob文件

 上传base64的


    

          // base64转文件
    

    

                function dataURLtoFile(dataurl, filename) {
    

    

                    var arr = dataurl.split(','), mime = arr[0].match(/:(.*?);/)[1],
    

    

                        bstr = atob(arr[1]), n = bstr.length, u8arr = new Uint8Array(n);
    

    

                    while (n--) {
    

    

                        u8arr[n] = bstr.charCodeAt(n);
    

    

                    }
    

    

                    return new File([u8arr], filename, {type: mime});
    

    

                }
    



 // $.ajax({
        //         type: 'POST',
        //         url: "/upload",
        //         data: dataURLtoFile(image, 'aa.png'),
        //         cache: false,
        //         processData: false,
        //         contentType: false,
        //         success: function (ret) {
        //             alert(ret);
        //         }
        //     });

        formdata = new FormData(),
                xhr = new XMLHttpRequest();

            formdata.append('fieldname',new Date().getTime()+'.png');  
            // 将文件添加到formdata对象中，（注：下面的file字段名在node中有用）
            formdata.append('file', dataURLtoFile(image, 'aa.png'));
            xhr.open("POST", "/upload", true);
            xhr.onreadystatechange = function () {
                if (xhr.readyState == 4 && xhr.status == 200) {
                   alert('ok')
                }
            }
            xhr.send(formdata);

app.post('/upload', function(req, res, next){
    var ws = fs.createWriteStream("./index.png", { encoding: "binary" });
    req.pipe(ws);

    res.send({ret_code: '0'});
});

或者：

var express = require('express');
 var app = express();
 var multer  = require('multer')
 var fs=require('fs')
  app.use('/static',express.static('./static'));

  var storage = multer.diskStorage({
    destination: function (req, file, cb) {
      cb(null, './upload')
    },
    filename: function (req, file, cb) {
      cb(null, file.fieldname + '-' + Date.now())
    }
  })
  var upload = multer({ storage });
app.post('/upload',upload.single('file'), function(req, res, next){
    // var ws = fs.createWriteStream("./index.png", { encoding: "binary" });
    // req.pipe(ws);

    console.log(req.body)
    res.send({ret_code: '0'});
});

  var server = app.listen(3000, 
    function () { console.log('Example app listening on port 3000!'); });