小编Cas*_*les的帖子

我一直在检查别人的CSS,我注意到他们正在做的事情我还没有见过...

body {font:14px/26px "Helvetica Neue", Arial, Helvetica, Geneva, sans-serif}

14px/26px有什么作用？我试图谷歌它,但似乎没有出现.

这没有延迟:

$connection = new MongoClient("mongodb://localhost:27017", array("replicaSet" => REPLICASET,'username'=>USER, 'password'=>PASSWORD, 'db'=>DATABASE));

但是,当我从副本集添加所有主机时,这最多需要10秒.PHP驱动程序(1.6.7)

$connection = new MongoClient("mongodb://".HOST_1.":27017,".HOST_2.":27017,".HOST_3.":27018", array("replicaSet" => REPLICASET,'username'=>USER, 'password'=>PASSWORD, 'db'=>DATABASE));

在日志中,延迟似乎在每个连接处.以下是日志的摘录:

[22-Jun-2015 12:04:41 Australia/ACT] PHP Notice:  CON     FINE: Connecting to tcp://ec2-XX-XXX-XXX-XXX.ap-southeast-2.compute.amazonaws.com:27017 (ec2-XX-XXX-XXX-XXX.ap-southeast-2.compute.amazonaws.com:27017;launch;launch/launch/55a850dad20e018890350ece678dc293;15873) with connection timeout: 60.000000 in /home/user/public_html/test.php on line 52
[22-Jun-2015 12:04:47 Australia/ACT] PHP Notice:  CON     INFO: stream_connect: Not establishing SSL for ec2-XX-XXX-XXX-XXX.ap-southeast-2.compute.amazonaws.com:27017 in /home/user/public_html/test.php on line 52

当我进入主服务器并尝试从终端快速连接时.

mongo --host "launch/host:27017,ec2-XX-XXX-XXX-XXX.ap-southeast-2.compute.amazonaws.com:27017,host2:27018" --authenticationDatabase launch -u USERNAME -p PASSWORD

为什么PHP需要这么长时间才能连接？

7月20日更新:

我已将主服务器上的mongo更新为2.6.10但我的测试页面仍需要5秒才能加载.这就是我试图连接的方式:

error_reporting(E_ALL);
MongoLog::setLevel(MongoLog::ALL);
MongoLog::setModule(MongoLog::ALL);

try {
    $connection = new …

为什么这些3D CSS平面在Firefox和Chrome中重叠而在Safari中不重叠？

http://jsfiddle.net/yNfQX/6/

..我怎么让它像safari一样？

Safari和Firefox预览版

我正在使用以下代码将iOS上的mp3转换为m4a:iOS swift将mp3转换为aac

但我需要将左右声道提取到单独的m4a文件中.

我有这个代码工作,它将我的音频分成nsdata:

let leftdata:NSMutableData! = NSMutableData()
let rightdata:NSMutableData! = NSMutableData()

let buff: CMBlockBufferRef = CMSampleBufferGetDataBuffer(sampleBuffer!)!

var lengthAtOffset: size_t = 0
var totalLength:Int = 0
var data: UnsafeMutablePointer<Int8> = nil

if( CMBlockBufferGetDataPointer( buff, 0, &lengthAtOffset, &totalLength, &data ) != noErr ) {
    print("some sort of error happened")
} else {

    for i in 0.stride(to: totalLength, by: 2) {

        if(i % 4 == 0) {
            leftdata.appendBytes(data+i, length: 2)
        } else {
            rightdata.appendBytes(data+i, length: 2)
        }

    }
} …

我最近发布了这个关于在 iOS 上使用多路由的问题，我以为我解决了它，但是我发现它不太有效：AVAudioEngine Multichannel mapping

我遇到的问题是多路由仅适用于前两个输出通道。我正在尝试使其适用于 4 通道音频接口。

我已经设法使用 AVAudioPlayer 将音频路由到 USB 接口的每个输出：

var avplayer = AVAudioPlayer()

@IBAction func avAudioPlayerPlay(_ sender: Any)
{
    let audioSession = AVAudioSession.sharedInstance()
    let route = audioSession.currentRoute

    // set the session category
    do
    {
        //try audioSession.setCategory(.multiRoute)
        try audioSession.setCategory(.multiRoute, options: .mixWithOthers)
    }
    catch
    {
        print("unable to set category", error)
        return
    }

    // activate the audio session - turns on multiroute I believe
    do
    {
        try audioSession.setActive(true)
        //try audioSession.setActive(true, options: .notifyOthersOnDeactivation)
    }
    catch
    {
        print("unable to set …

我一直在尝试使用ImageMagick复制Photoshops颜色混合模式.我在在线指南中找到了以下公式,但我不知道它们的含义.我只需要交换某些频道吗？

我正在使用基于此的代码在Swift 中将mp3转换为m4a。

当我生成PCM文件时，它可以工作。当我将导出格式更改为m4a时，它将生成一个文件，但无法播放。为什么会腐败？

这是到目前为止的代码：

import AVFoundation
import UIKit

class ViewController: UIViewController {

    var rwAudioSerializationQueue:dispatch_queue_t!

    var asset:AVAsset!

    var assetReader:AVAssetReader!

    var assetReaderAudioOutput:AVAssetReaderTrackOutput!

    var assetWriter:AVAssetWriter!

    var assetWriterAudioInput:AVAssetWriterInput!

    var outputURL:NSURL!

    override func viewDidLoad() {
        super.viewDidLoad()

        let rwAudioSerializationQueueDescription = String(self) + " rw audio serialization queue"

        // Create the serialization queue to use for reading and writing the audio data.
        self.rwAudioSerializationQueue = dispatch_queue_create(rwAudioSerializationQueueDescription, nil)

        let paths = NSSearchPathForDirectoriesInDomains(.DocumentDirectory, .UserDomainMask, true)
        let documentsPath = paths[0]

        print(NSBundle.mainBundle().pathForResource("input", ofType: "mp3"))

        self.asset = …

如何从此UISlider中移除发光/阴影？