在应用程序.js主文件中未定义的字符串 - NodeJS



我正在尝试获取上传文件的文件名,但是在nodejs的主应用程序文件中进行如下字符串操作时出现错误:

var fileName = file.split('path:')[1]
.split('',')[0]
.split(dir)[1]
.toString()
.replace(/\/g, '')
.replace(///g, '');

我在.toString()时出错,不知道为什么。

错误堆栈跟踪

TypeError: Cannot read property 'toString' of undefined
at C:UsersmurliNodeProjectsSpeechExpressapp.js:57:76
at IncomingForm.<anonymous> (C:UsersmurliNodeProjectsSpeechExpressnode_modulesformidablelibincoming_form.js:105:9)
at emitNone (events.js:86:13)
at IncomingForm.emit (events.js:185:7)
at IncomingForm._maybeEnd (C:UsersmurliNodeProjectsSpeechExpressnode_modulesformidablelibincoming_form.js:553:8)
at C:UsersmurliNodeProjectsSpeechExpressnode_modulesformidablelibincoming_form.js:230:12
at WriteStream.<anonymous> (C:UsersmurliNodeProjectsSpeechExpressnode_modulesformidablelibfile.js:74:5)
at WriteStream.g (events.js:291:16)
at emitNone (events.js:91:20)
at WriteStream.emit (events.js:185:7)

法典

app.use('/uploadFile', function(request, response){
// parse a file upload
var mime = require('mime');
var formidable = require('formidable');
var util = require('util');
var form = new formidable.IncomingForm();
var dir = !!process.platform.match(/^win/) ? '\public\uploads\' : '/public/uploads/';
form.uploadDir = __dirname + dir;
console.log("Test 99: " + form.uploadDir);
form.keepExtensions = true;
form.maxFieldsSize = 10 * 1024 * 1024;
form.maxFields = 1000;
form.multiples = false;
console.log("Test 100: ");
form.parse(request, function(err, fields, files) {
var file = util.inspect(files);
console.log("form parse file: "+file + "n" + files);
response.writeHead(200, getHeaders('Content-Type', 'application/json'));

var fileName = file.split('path:')[1].split('',')[0].split(dir)[1].toString().replace(/\/g, '').replace(///g, '');
var fileURL = 'http://' + app.address + ':' + port + '/public/uploads/' + fileName;
console.log('fileURL: ', fileURL);
response.write(JSON.stringify({
fileURL: fileURL
}));
response.end();
});
});

文件内容

{ file:
File {
domain: null,
_events: {},
_eventsCount: 0,
_maxListeners: undefined,
size: 114898,
path: 'C:\Users\username\NodeProjects\SpeechExpress\public\uploads\upload_3c927e85105d0fd5d873e84952821531.webm',
name: '1234.webm',
type: 'video/webm',
hash: null,
lastModifiedDate: 2017-09-19T22:18:03.330Z,
_writeStream:
WriteStream {
_writableState: [Object],
writable: false,
domain: null,
_events: {},
_eventsCount: 0,
_maxListeners: undefined,
path: 'C:\Users\username\NodeProjects\SpeechExpress\public\uploads\upload_3c927e85105d0fd5d873e84952821531.webm',
fd: null,
flags: 'w',
mode: 438,
start: undefined,
autoClose: true,
pos: undefined,
bytesWritten: 114898,
closed: true } } }

我所需要的只是这个

upload_3c927e85105d0fd5d873e84952821531.webm

由此

C:\Users\username\NodeProjects\SpeechExpress\public\uploads\upload_3c927e85105d0fd5d873e84952821531.webm

这个问题有两个问题。

首先是如何从完整的目录字符串中提取文件名。 因为你使用节点.js,它带有一个方便的功能path.basename(filename)

第二个问题,是如何首先获得路径。 强大的提供文件,这是一个包含所有文件的简单对象文字。 您的文件输入名称似乎称为 file,..因此,要访问该路径,您可以执行files.file.path

因此,在将两者结合起来之后,我们有..path.basename(files.file.path),您应该获取文件名,在本例中为 ->upload_3c927e85105d0fd5d873e84952821531.webm

什么不省得自己头痛就用path.basename

从文档中:

var path = require('path');
path.basename('/foo/bar/baz/asdf/quux.html');
// Returns: 'quux.html'
path.basename('/foo/bar/baz/asdf/quux.html', '.html');
// Returns: 'quux'

这样做

var f = File.path.split('\');
var fileName = f[f.length-1];

我所需要的只是这个

upload_3c927e85105d0fd5d873e84952821531.webm

由此

C:\Users\username\NodeProjects\SpeechExpress\public\uploads\upload_3c927e85105d0fd5d873e84952821531.webm

然后简单地:

let path = 'C:\Users\username\NodeProjects\SpeechExpress\public\uploads\upload_3c927e85105d0fd5d873e84952821531.webm',
filename = path.split('\').pop();

并将path替换为正确的参考

我建议你使用正则表达式来处理它。

E:G

let file = 'C:\Users\username\NodeProjects\SpeechExpress\public\uploads\upload_3c927e85105d0fd5d873e84952821531.webm'
let fileName = file.match(/upload_w+.webm$/)[0];
let fileURL = 'http://' + app.address + ':' + port + '/public/uploads/' + fileName;
// ....The rest of the code.

您似乎使用node,因此我建议您使用官方路径对象:

const path = require("path")
const myFileName = "C:\Users\username\NodeProjects\SpeechExpress\public\uploads\upload_3c927e85105d0fd5d873e84952821531.webm"
const unixFile = "/home/test/jhgfd.h"
const obj = path.parse(myFileName)
console.log(obj.name)
console.log(obj)

最好的是它也可以在Linux上运行。所需的属性称为 name。

最新更新