vue hello world项目
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Flexible ascii progress bar.
## Installation
```bash
$ npm install progress
```
## Usage
First we create a `ProgressBar`, giving it a format string
as well as the `total`, telling the progress bar when it will
be considered complete. After that all we need to do is `tick()` appropriately.
```javascript
var ProgressBar = require('progress');
var bar = new ProgressBar(':bar', { total: 10 });
var timer = setInterval(function () {
bar.tick();
if (bar.complete) {
console.log('\ncomplete\n');
clearInterval(timer);
}
}, 100);
```
### Options
These are keys in the options object you can pass to the progress bar along with
`total` as seen in the example above.
- `curr` current completed index
- `total` total number of ticks to complete
- `width` the displayed width of the progress bar defaulting to total
- `stream` the output stream defaulting to stderr
- `head` head character defaulting to complete character
- `complete` completion character defaulting to "="
- `incomplete` incomplete character defaulting to "-"
- `renderThrottle` minimum time between updates in milliseconds defaulting to 16
- `clear` option to clear the bar on completion defaulting to false
- `callback` optional function to call when the progress bar completes
### Tokens
These are tokens you can use in the format of your progress bar.
- `:bar` the progress bar itself
- `:current` current tick number
- `:total` total ticks
- `:elapsed` time elapsed in seconds
- `:percent` completion percentage
- `:eta` estimated completion time in seconds
- `:rate` rate of ticks per second
### Custom Tokens
You can define custom tokens by adding a `{'name': value}` object parameter to your method (`tick()`, `update()`, etc.) calls.
```javascript
var bar = new ProgressBar(':current: :token1 :token2', { total: 3 })
bar.tick({
'token1': "Hello",
'token2': "World!\n"
})
bar.tick(2, {
'token1': "Goodbye",
'token2': "World!"
})
```
The above example would result in the output below.
```
1: Hello World!
3: Goodbye World!
```
## Examples
### Download
In our download example each tick has a variable influence, so we pass the chunk
length which adjusts the progress bar appropriately relative to the total
length.
```javascript
var ProgressBar = require('progress');
var https = require('https');
var req = https.request({
host: 'download.github.com',
port: 443,
path: '/visionmedia-node-jscoverage-0d4608a.zip'
});
req.on('response', function(res){
var len = parseInt(res.headers['content-length'], 10);
console.log();
var bar = new ProgressBar(' downloading [:bar] :rate/bps :percent :etas', {
complete: '=',
incomplete: ' ',
width: 20,
total: len
});
res.on('data', function (chunk) {
bar.tick(chunk.length);
});
res.on('end', function () {
console.log('\n');
});
});
req.end();
```
The above example result in a progress bar like the one below.
```
downloading [===== ] 39/bps 29% 3.7s
```
### Interrupt
To display a message during progress bar execution, use `interrupt()`
```javascript
var ProgressBar = require('progress');
var bar = new ProgressBar(':bar :current/:total', { total: 10 });
var timer = setInterval(function () {
bar.tick();
if (bar.complete) {
clearInterval(timer);
} else if (bar.curr === 5) {
bar.interrupt('this message appears above the progress bar\ncurrent progress is ' + bar.curr + '/' + bar.total);
}
}, 1000);
```
You can see more examples in the `examples` folder.
## License
MIT