JavaScript:解析奇数字符串以获取必要的信息(RegEx)

Question

我正在尝试解析一个格式奇怪的字符串，该字符串存储了我正在构建的音频播放器所需的一些数据。一个例子是:

"a:14:{s:10:"dataformat";s:3:"mp3";s:8:"channels";i:2;s:11:"sample_rate";i:44100;s:7:"bitrate";i:192000;s:11:"channelmode";s:12:"joint stereo";s:12:"bitrate_mode";s:3:"cbr";s:8:"lossless";b:0;s:15:"encoder_options";s:6:"CBR192";s:17:"compression_ratio";d:0.1360544217687074952660708504481590352952480316162109375;s:10:"fileformat";s:3:"mp3";s:8:"filesize";i:7249920;s:9:"mime_type";s:10:"audio/mpeg";s:6:"length";i:302;s:16:"length_formatted";s:4:"5:02";}"

太丑了。对于我与之交互的每首歌曲，都会包含上面提供的信息类型。基本上我想要的只是“length_formatted”的值，即“5:02”。我假设我需要使用正则表达式来完成此任务，但由于没有任何经验，我不确定从哪里开始。

Answer 1

试试这个代码:

string = `"a:14:{s:10:"dataformat";s:3:"mp3";s:8:"channels";i:2;s:11:"sample_rate";i:44100;s:7:"bitrate";i:192000;s:11:"channelmode";s:12:"joint stereo";s:12:"bitrate_mode";s:3:"cbr";s:8:"lossless";b:0;s:15:"encoder_options";s:6:"CBR192";s:17:"compression_ratio";d:0.1360544217687074952660708504481590352952480316162109375;s:10:"fileformat";s:3:"mp3";s:8:"filesize";i:7249920;s:9:"mime_type";s:10:"audio/mpeg";s:6:"length";i:302;s:16:"length_formatted";s:4:"5:02";}"`

document.body.innerHTML = string.match(/length_formatted.*?(\d+:\d+)/)[1]

解释正则表达式:

/length_formatted.*?(\d+:\d+)/

length_formatted          // match the literal text
.*?                       // till the next ocurrence of
(                         // group in [1]
    \d+                       // at least one digit
    :                         // literal ':'
    \d+                       // at least one digit
)                         // end of captouring group

希望有帮助。