node 单文件或多文件上传

解析form表单插件 formidable

例子：

前台 html:

//form表单提交(页面会刷新)
<form action="http://127.0.0.1:3000/test" method="post" enctype="multipart/form-data">
    <input type="file" id="" name="upload" multiple="multiple"/> <br />
    <input type="text" name="username"/>
    <input type="submit" value="Upload" />
</form>

//ajax提交from表单（无页面刷新）
<form id="uploadForm">
    <input type="file" id="upload" name="upload" multiple="multiple"/> <br />
    <input type="text" name="username"/>
    <input type="button" value="上传" onclick='shangchuan()'/>
</form>
<script src='http://libs.baidu.com/jquery/2.1.1/jquery.min.js'></script>
<script type="text/javascript">
    function shangchuan(){
        var formData = new FormData($("#uploadForm")[0]);
        $.ajax({
            url: 'http://127.0.0.1:3000/test' ,
            type: 'POST',
            data: formData,
            async: false,
            cache: false,
            contentType: false,
            processData: false,
            success: function (value) {
               console.log(value)
            },
            error: function (err) {
                console.log(err)
            }
        });
    }
</script>

服务端 node（返回上传文件路径名）

exports.test = function (req, res) {
var form = new formidable.IncomingForm();
    form.encoding = 'utf-8'
    form.keepExtensions = true //保留后缀名
    form.uploadDir = "./public/" //上传路径
    form.multiples = true; //多图上传
//多文件存储到 files
    var files = []
    form.on('file', function (filed, file) {
        files.push([filed, file]);
    })
//解析form表单 fields为表单中非文件内容   files为文件信息
    form.parse(req, function (err, fields, files) {
        console.log(fields)
        var paths = []
//单文件
        if (typeof(files.upload.length) === "undefined") {
           let path = files.upload.path.replace(/public/g, '')
            path = config + path.replace(/\\/g, '/')
            paths.push(path)
            res.json({paths: paths})
        } else {
//多文件
            for (let i = 0; i < files.upload.length; i++) {
               let path = files.upload[i].path.replace(/public/g, '')
                path = config + path.replace(/\\/g, '/')
                paths.push(path)
            }
            res.json({paths: paths})
        }
    })
}

//解析base64,上传图片（前台向后台传base64数组）
function upload(req,res){
        var imgs=req.body.imgs
        var paths=[]
        for(var i=0;i<imgs.length;i++){
            //将前台传来的base64数据去掉前缀
            var img = imgs[i].replace(/^data:image\/\w+;base64,/, '');
            var imgBuffer = new Buffer(img, 'base64');
            var path = 'public/images'+ Date.now() +'.png'
            paths.push(path)
            //写入文件
            fs.writeFile(path, imgBuffer,function(err,date){
                if(err){
                    console.log(err)
                }
                if(paths.length==imgs.length){
                    res.json({code:200,result:paths})
                }
            });
        }
    }

以前用Java写过图片上传，一对比，感觉node要比Java写上传简单点，formidable详细配置请看官方文档