javascript 无法读取未定义的属性“main”
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Cannot read property 'main' of undefined
提问by Joshua Barnett
So my project structures is I have a srcand wwwdirectory in my root ./, which also contains my bower.json, gulpfile.js, and .bowerrcwith the directoryset to ./www/bower/.
所以我的项目结构是我有一个src和www目录在我的根./，其中还包含我的bower.json，gulpfile.js和.bowerrc与directory设置为./www/bower/。
I have an index.htmlin my ./srcand I've setup a gulp task that pipes it through wiredepand out to the ./wwwwhere the bower packages are.
我有一个index.html，我./src已经设置了一个 gulp 任务，将它通过管道输送wiredep到./www凉亭包所在的位置。
Unfortunately it adds all the dependecies as if it's in the ./srcdirectory so all of them are prefixed like ../www/bower/which does work as the final index.htmlends up in the wwwdirectory so I fiddled with some of the wiredepconfiguration options like so:
不幸的是，它添加了所有依赖项，就好像它在./src目录中一样，因此所有依赖项都带有前缀，就像../www/bower/最终index.html在www目录中一样起作用，所以我摆弄了一些wiredep配置选项，如下所示：
gulp.task('bower', function () {
gulp.src('./src/index.html')
.pipe(wiredep({
cwd: './www',
bowerJson: require('./bower.json'),
directory: '../.bowerrc'
}))
.pipe(gulp.dest('./www'));
});
However I get the following error:
但是我收到以下错误：
stream.js:94
throw er; // Unhandled stream error in pipe.
^
TypeError: Cannot read property 'main' of undefined
at findMainFiles (D:\Dropbox\University\MindFlipDOM\node_modules\wiredep\lib\detect-dependencies.js:53:37)
at D:\Dropbox\University\MindFlipDOM\node_modules\wiredep\lib\detect-dependencies.js:111:17
at forOwn (D:\Dropbox\University\MindFlipDOM\node_modules\wiredep\node_modules\lodash\dist\lodash.js:1301:15)
at Function.forEach (D:\Dropbox\University\MindFlipDOM\node_modules\wiredep\node_modules\lodash\dist\lodash.js:2595:9)
at detect (D:\Dropbox\University\MindFlipDOM\node_modules\wiredep\lib\detect-dependencies.js:312:5)
at wiredep (D:\Dropbox\University\MindFlipDOM\node_modules\wiredep\wiredep.js:178:39)
at Transform._transform (D:\Dropbox\University\MindFlipDOM\node_modules\wiredep\wiredep.js:217:34)
at Transform._read (D:\Dropbox\University\MindFlipDOM\node_modules\wiredep\node_modules\through2\node_modules\readable-stream\lib\_stream_transform.js:184:10)
at Transform._write (D:\Dropbox\University\MindFlipDOM\node_modules\wiredep\node_modules\through2\node_modules\readable-stream\lib\_stream_transform.js:172:12)
at doWrite (D:\Dropbox\University\MindFlipDOM\node_modules\wiredep\node_modules\through2\node_modules\readable-stream\lib\_stream_writable.js:238:10)
So what am I doing wrong?
那我做错了什么？
回答by Chandramuralis
Also try, this will make sure to download the necessary modules that were missing.
也尝试一下，这将确保下载丢失的必要模块。
bower install
回答by Bipin Bhandari
Well as far as I can guess, you messed up with bower. Most likely you uninstalled a dependency and forgot to save.
好吧，据我所知，你把 bower 搞砸了。很可能您卸载了依赖项而忘记保存。
What you should have done:
你应该做的：
bower uninstall <dependency> --save
What you probably did:
你可能做了什么：
bower uninstall <dependency>
You can solve this issue by bower executing uninstall <dependency> --saveor if you are unsure of which components you uninstalled, you can edit bower.jsonfile and remove components that are not installed. (You can check if a dependency is installed in bower_componenetsdirectory)
您可以通过执行 bower 来解决此问题，uninstall <dependency> --save或者如果您不确定卸载了哪些组件，您可以编辑bower.json文件并删除未安装的组件。（您可以检查bower_componenets目录中是否安装了依赖项）
