文件上传总是失败 返回下面的内容

object(Symfony\Component\HttpFoundation\File\UploadedFile)#27 (7) { ["test":"Symfony\Component\HttpFoundation\File\UploadedFile":private]=> bool(false) ["originalName":"Symfony\Component\HttpFoundation\File\UploadedFile":private]=> string(6) "1.html" ["mimeType":"Symfony\Component\HttpFoundation\File\UploadedFile":private]=> string(9) "text/html" ["size":"Symfony\Component\HttpFoundation\File\UploadedFile":private]=> int(4757) ["error":"Symfony\Component\HttpFoundation\File\UploadedFile":private]=> int(0) ["pathName":"SplFileInfo":private]=> string(14) "/tmp/phpulGyl7" ["fileName":"SplFileInfo":private]=> string(9) "phpulGyl7" }