• ▸ PHP
• ▸ Java
• ▸ Java SE
• ▸ Python
• ▸ C#
• ▸ C&C++
• ▸ Ruby
• ▸ VB
• ▸ asp.Net
• ▸ Go
• ▸ Perl
• ▸ netty
• ▸ Django
• ▸ Delphi
• ▸ Jsp
• ▸ .NET Core
• ▸ Spring
• ▸ Flask
• ▸ Springboot
• ▸ SpringMVC
• ▸ Lua
• ▸ Laravel
• ▸ Mybatis
• ▸ Asp
• ▸ Groovy
• ▸ ThinkPHP
• ▸ Yii
• ▸ swoole
• ▸ HTML
• ▸ HTML5
• ▸ JavaScript
• ▸ CSS
• ▸ jQuery
• ▸ Bootstrap
• ▸ Angularjs
• ▸ TypeScript
• ▸ Vue
• ▸ Dojo
• ▸ Json
• ▸ Electron
• ▸ Node.js
• ▸ extjs
• ▸ Express
• ▸ XML
• ▸ ES6
• ▸ Ajax
• ▸ Flash
• ▸ Unity
• ▸ React
• ▸ Flex
• ▸ Ant Design
• ▸ Web前端
• ▸ 微信小程序
• ▸ 微信公众号
• ▸ iOS
• ▸ Android
• ▸ Swift
• ▸ Hybrid
• ▸ Cocos2d-x
• ▸ Flutter
• ▸ Xcode
• ▸ Silverlight
• ▸ cocoa
• ▸ Cordova

• 前端之家
• Swift
• 如何压缩缩小图像的大小,然后上传到Parse作为PFFile？ (迅速)

override func prepareForSegue(segue: UIStoryboardSegue,sender: AnyObject?) {
    if (segue.identifier == "getImage")
    {
        var svc = segue.destinationViewController as! ClothesDetail
        svc.imagePassed = imageView.image
    }
}

let imageData = UIImagePNGRepresentation(imagePassed)
let imageFile = PFFile(name: "\(picName).png",data: imageData)

var userpic = PFObject(className:"UserPic")
userpic["picImage"] = imageFile`

Xcode 8.2•Swift 3.0.2

extension UIImage {
    enum JPEGQuality: CGFloat {
        case lowest  = 0
        case low     = 0.25
        case medium  = 0.5
        case high    = 0.75
        case highest = 1
    }

    /// Returns the data for the specified image in PNG format
    /// If the image object’s underlying image data has been purged,calling this function forces that data to be reloaded into memory.
    /// - returns: A data object containing the PNG data,or nil if there was a problem generating the data. This function may return nil if the image has no data or if the underlying CGImageRef contains data in an unsupported bitmap format.
    var png: Data? { return UIImagePNGRepresentation(self) }

    /// Returns the data for the specified image in JPEG format.
    /// If the image object’s underlying image data has been purged,calling this function forces that data to be reloaded into memory.
    /// - returns: A data object containing the JPEG data,or nil if there was a problem generating the data. This function may return nil if the image has no data or if the underlying CGImageRef contains data in an unsupported bitmap format.
    func jpeg(_ quality: JPEGQuality) -> Data? {
        return UIImageJPEGRepresentation(self,quality.rawValue)
    }
}

用法：

if let imageData = image.jpeg(.lowest) {
    print(imageData.count)
}

Swift 2.3

extension UIImage {
    var uncompressedpnGData: NSData?      { return UIImagePNGRepresentation(self)        }
    var highestQualityJPEGNSData: NSData? { return UIImageJPEGRepresentation(self,1.0)  }
    var highQualityJPEGNSData: NSData?    { return UIImageJPEGRepresentation(self,0.75) }
    var mediumQualityJPEGNSData: NSData?  { return UIImageJPEGRepresentation(self,0.5)  }
    var lowQualityJPEGNSData: NSData?     { return UIImageJPEGRepresentation(self,0.25) }
    var lowestQualityJPEGNSData:NSData?   { return UIImageJPEGRepresentation(self,0.0)  }
}

然后你可以这样使用它：

if let imageData = image.lowestQualityJPEGNSData {
    print(imageData.length)
}