问题
Mozilla Developer Center's HTML5 media guide describes an event for audio and video elements called "loadedmetadata". Is there anyway to get the metadata for files? I am writing an HTML5 extension for Google Chrome and I don't know what the metadata for the audio files I'm creating a player for beforehand.
Edit: This question seems to be kicking everyone's ass. :/
回答1:
According to this you can use filereader.readAsBinaryString(file); to get the binary data of the ID3 tag.
filereader.readAsBinaryString(file); will asynchronously return a binary string with each byte represented by an integer in the range [0..255]. This is useful for binary manipulations of a file’s data, for example to look for ID3 tags in an MP3 file, or to look for EXIF data in a JPEG image.
来源：https://stackoverflow.com/questions/2244806/is-there-anyway-to-get-id3-metadata-from-an-mp3-or-vorbis-comments-from-ogg-via