PS：Xcode 版本是 Version 9.2 (9C40b)，编译 Swift 版本是：3.2
NSObject+ClassName
功能：获取某个对象或者某个类的类名字符串（比如 xib 加载）
extension NSObject { /// 返回类名字符串 static var className: String { return String(describing: self) } /// 返回类名字符串 var className: String { return String(describing: type(of: self)) }}复制代码 String+BoundingRect
功能：计算字符串在 label 上的宽高（比如 cell 自适应高度）
extension String { /// 给定最大宽计算高度，传入字体、行距、对齐方式（便捷调用） func heightForLabel(width: CGFloat, font: UIFont, lineSpacing: CGFloat = 5, alignment: NSTextAlignment = .left) -> CGFloat { let paragraphStyle = NSMutableParagraphStyle() paragraphStyle.lineSpacing = lineSpacing paragraphStyle.alignment = alignment let attributes: [String : Any] = [ NSFontAttributeName: font, NSParagraphStyleAttributeName: paragraphStyle ] let textSize = textSizeForLabel(width: width, height: CGFloat(Float.greatestFiniteMagnitude), attributes: attributes) return textSize.height } /// 给定最大宽计算高度，传入属性字典（便捷调用） func heightForLabel(width: CGFloat, attributes: [String: Any]) -> CGFloat { let textSize = textSizeForLabel(width: width, height: CGFloat(Float.greatestFiniteMagnitude), attributes: attributes) return textSize.height } /// 给定最大高计算宽度，传入字体（便捷调用） func widthForLabel(height: CGFloat, font: UIFont) -> CGFloat { let labelTextAttributes = [NSFontAttributeName: font] let textSize = textSizeForLabel(width: CGFloat(Float.greatestFiniteMagnitude), height: height, attributes: labelTextAttributes) return textSize.width } /// 给定最大高计算宽度，传入属性字典（便捷调用） func widthForLabel(height: CGFloat, attributes: [String: Any]) -> CGFloat { let textSize = textSizeForLabel(width: CGFloat(Float.greatestFiniteMagnitude), height: height, attributes: attributes) return textSize.width } /// 给定最大宽高计算宽度和高度，传入字体、行距、对齐方式（便捷调用） func textSizeForLabel(width: CGFloat, height: CGFloat, font: UIFont, lineSpacing: CGFloat = 5, alignment: NSTextAlignment = .left) -> CGSize { let paragraphStyle = NSMutableParagraphStyle() paragraphStyle.lineSpacing = lineSpacing paragraphStyle.alignment = alignment let attributes: [String : Any] = [ NSFontAttributeName: font, NSParagraphStyleAttributeName: paragraphStyle ] let textSize = textSizeForLabel(width: width, height: height, attributes: attributes) return textSize } /// 给定最大宽高计算宽度和高度，传入属性字典（便捷调用） func textSizeForLabel(size: CGSize, attributes: [String: Any]) -> CGSize { let textSize = textSizeForLabel(width: size.width, height: size.height, attributes: attributes) return textSize } /// 给定最大宽高计算宽度和高度，传入属性字典（核心) func textSizeForLabel(width: CGFloat, height: CGFloat, attributes: [String: Any]) -> CGSize { let defaultOptions: NSStringDrawingOptions = [.usesLineFragmentOrigin, .usesFontLeading] let maxSize = CGSize(width: width, height: height) let rect = self.boundingRect(with: maxSize, options: defaultOptions, attributes: attributes, context: nil) let textWidth: CGFloat = CGFloat(Int(rect.width) + 1) let textHeight: CGFloat = CGFloat(Int(rect.height) + 1) return CGSize(width: textWidth, height: textHeight) }}extension NSAttributedString { /// 根据最大宽计算高度（便捷调用) func heightForLabel(width: CGFloat) -> CGFloat { let textSize = textSizeForLabel(width: width, height: CGFloat(Float.greatestFiniteMagnitude)) return textSize.height } /// 根据最大高计算宽度（便捷调用) func widthForLabel(height: CGFloat) -> CGFloat { let textSize = textSizeForLabel(width: CGFloat(Float.greatestFiniteMagnitude), height: height) return textSize.width } /// 计算宽度和高度（核心) func textSizeForLabel(width: CGFloat, height: CGFloat) -> CGSize { let defaultOptions: NSStringDrawingOptions = [.usesLineFragmentOrigin, .usesFontLeading] let maxSize = CGSize(width: width, height: height) let rect = self.boundingRect(with: maxSize, options: defaultOptions, context: nil) let textWidth: CGFloat = CGFloat(Int(rect.width) + 1) let textHeight: CGFloat = CGFloat(Int(rect.height) + 1) return CGSize(width: textWidth, height: textHeight) }}复制代码 String+RegularExpression
功能：主要是简化和统一外部使用正则表达式
extension String { /// 通过正则表达式匹配替换 func replacingStringOfRegularExpression(pattern: String, template: String) -> String { var content = self do { let range = NSRange(location: 0, length: content.count) let expression = try NSRegularExpression(pattern: pattern, options: .caseInsensitive) content = expression.stringByReplacingMatches(in: content, options: .reportCompletion, range: range, withTemplate: template) } catch { print("regular expression error") } return content } /// 通过正则表达式匹配返回结果 func matches(pattern: String) -> [NSTextCheckingResult] { do { let range = NSRange(location: 0, length: count) let expression = try NSRegularExpression(pattern: pattern, options: .caseInsensitive) let matchResults = expression.matches(in: self, options: .reportCompletion, range: range) return matchResults } catch { print("regular expression error") } return [] } /// 通过正则表达式返回第一个匹配结果 func firstMatch(pattern: String) -> NSTextCheckingResult? { do { let range = NSRange(location: 0, length: count) let expression = try NSRegularExpression(pattern: pattern, options: .caseInsensitive) let match = expression.firstMatch(in: self, options: .reportCompletion, range: range) return match } catch { print("regular expression error") } return nil }}复制代码 String+Substr
功能：字符串截取快捷方法，你懂的(⊙o⊙)…
extension String { /// 寻找在 startString 和 endString 之间的字符串 func substring(between startString: String, and endString: String?, options: String.CompareOptions = .caseInsensitive) -> String? { let range = self.range(of: startString, options: options) if let startIndex = range?.upperBound { let string = self.substring(from: startIndex) if let endString = endString { let range = string.range(of: endString, options: options) if let startIndex = range?.lowerBound { return string.substring(to: startIndex) } } return string } return nil } /// 寻找 prefix 字符串，并返回从 prefix 到尾部的字符串 func substring(prefix: String, options: String.CompareOptions = .caseInsensitive, isContain: Bool = true) -> String? { let range = self.range(of: prefix, options: options) if let startIndex = range?.upperBound { var resultString = self.substring(from: startIndex) if isContain { resultString = "\(prefix)\(resultString)" } return resultString } return nil } /// 寻找 suffix 字符串，并返回从头部到 suffix 位置的字符串 func substring(suffix: String, options: String.CompareOptions = .caseInsensitive, isContain: Bool = false) -> String? { let range = self.range(of: suffix, options: options) if let startIndex = range?.lowerBound { var resultString = self.substring(to: startIndex) if isContain { resultString = "\(resultString)\(suffix)" } return resultString } return nil } /// 从 N 位置到尾位置的字符串 func substring(from: IndexDistance) -> String? { let index = self.index(self.startIndex, offsetBy: from) return self.substring(from: index) } /// 从头位置到 N 位置的字符串 func substring(to: IndexDistance) -> String? { let index = self.index(self.startIndex, offsetBy: to) return self.substring(to: index) } /// 以 lower 为起点，偏移 range 得到的字符串 func substring(_ lower: IndexDistance, _ range: IndexDistance) -> String? { let lowerIndex = self.index(self.startIndex, offsetBy: lower) let upperIndex = self.index(lowerIndex, offsetBy: range) let range = Range(uncheckedBounds: (lowerIndex, upperIndex)) return self.substring(with: range) }}复制代码 UIFont+Convenience
功能：除了简化自定义字体的引入外，这里可以统一管理字体大小，比如对字体大小进行统一屏幕适配
enum FontWeight: String { case light = "Light" case regular = "Regular" case medium = "Medium" case semibold = "Semibold" case bold = "Bold" case heavy = "Heavy"}enum FontType: String { case PingFangSC = "PingFangSC" case SFProText = "SFProText"}extension UIFont { static func heavyFont(ofSize fontSize: CGFloat, type: FontType = .PingFangSC) -> UIFont { return customFont(type, weight: .heavy, fontSize: fontSize) } static func regularFont(ofSize fontSize: CGFloat, type: FontType = .PingFangSC) -> UIFont { return customFont(type, weight: .regular, fontSize: fontSize) } static func boldFont(ofSize fontSize: CGFloat, type: FontType = .PingFangSC) -> UIFont { return customFont(type, weight: .bold, fontSize: fontSize) } static func lightFont(ofSize fontSize: CGFloat, type: FontType = .PingFangSC) -> UIFont { return customFont(type, weight: .light, fontSize: fontSize) } static func mediumFont(ofSize fontSize: CGFloat, type: FontType = .PingFangSC) -> UIFont { return customFont(type, weight: .medium, fontSize: fontSize) } static func semiboldFont(ofSize fontSize: CGFloat, type: FontType = .PingFangSC) -> UIFont { return customFont(type, weight: .semibold, fontSize: fontSize) } /// 自定义字体 static func customFont(_ type: FontType, weight: FontWeight, fontSize: CGFloat) -> UIFont { let realFontSize = fontSize if let customFont = UIFont(name: "\(type.rawValue)-\(weight.rawValue)", size: realFontSize) { return customFont } if #available(iOS 8.2, *) { var systemWeight: CGFloat = UIFontWeightRegular switch weight { case .light: systemWeight = UIFontWeightLight case .regular: systemWeight = UIFontWeightRegular case .medium: systemWeight = UIFontWeightMedium case .semibold: systemWeight = UIFontWeightSemibold case .bold: systemWeight = UIFontWeightBold case .heavy: systemWeight = UIFontWeightHeavy } return UIFont.systemFont(ofSize: realFontSize, weight: systemWeight) } else { return UIFont.systemFont(ofSize: realFontSize) } }}复制代码 UIView+Convenience
功能：一些常用的视图操作，比如 xib 加载、截图、找响应控制器
extension UIView { /// 从 xib 中加载视图 func loadViewFromNib(index: Int = 0) -> UIView? { let classInstance = type(of: self) let nibName = classInstance.className let nib = UINib(nibName: nibName, bundle: nil) if let views = nib.instantiate(withOwner: self, options: nil) as? [UIView] { return views.safeIndex(index) } return nil } /// 寻找当前视图所在的控制器 var responderController: UIViewController? { var nextReponder: UIResponder? = self.next while nextReponder != nil { if let viewController = nextReponder as? UIViewController { return viewController } nextReponder = nextReponder?.next } return nil } /// 生成视图的截图 func displayViewToImage() -> UIImage? { UIGraphicsBeginImageContextWithOptions(self.bounds.size, false, 0) if let context = UIGraphicsGetCurrentContext() { self.layer.render(in: context) } let image = UIGraphicsGetImageFromCurrentImageContext() UIGraphicsEndImageContext() return image }}复制代码 CollectionView+Convenience
功能：主要是为了简化 CollectionView 注册和从缓冲池取控件的代码
extension UICollectionView { /// 批量注册 Cell func registerForCells (_ cellClasses: [T.Type], isNib: Bool = true) { cellClasses.forEach { cellClass in registerForCell(cellClass, isNib: isNib) } } /// 注册 Cell func registerForCell (_ cellClass: T.Type, identifier: String? = nil, isNib: Bool = true) { let nibName = cellClass.className let cellIdentifier = identifier ?? nibName if isNib { self.register(UINib(nibName: nibName, bundle: nil), forCellWithReuseIdentifier: cellIdentifier) } else { self.register(cellClass, forCellWithReuseIdentifier: cellIdentifier) } } /// 注册顶部视图 func registerForHeader (_ cellClass: T.Type, identifier: String? = nil, isNib: Bool = true) { let nibName = cellClass.className let headerIdentifier = identifier ?? nibName if isNib { self.register(UINib(nibName: nibName, bundle: nil), forSupplementaryViewOfKind: UICollectionElementKindSectionHeader, withReuseIdentifier: headerIdentifier) } else { self.register(cellClass, forSupplementaryViewOfKind: UICollectionElementKindSectionHeader, withReuseIdentifier: headerIdentifier) } } /// 注册底部视图 func registerForFooter (_ cellClass: T.Type, identifier: String? = nil, isNib: Bool = true) { let nibName = cellClass.className let footerIdentifier = identifier ?? nibName if isNib { self.register(UINib(nibName: nibName, bundle: nil), forSupplementaryViewOfKind: UICollectionElementKindSectionFooter, withReuseIdentifier: footerIdentifier) } else { self.register(cellClass, forSupplementaryViewOfKind: UICollectionElementKindSectionFooter, withReuseIdentifier: footerIdentifier) } } /// 从缓存池取出 Cell func dequeueCell (_ cellClass: T.Type, reuseIdentifier: String? = nil, indexPath: IndexPath) -> T { let identifier: String = reuseIdentifier ?? cellClass.className if let cell = dequeueReusableCell(withReuseIdentifier: identifier, for: indexPath) as? T { return cell } else { return T() } } /// 从缓存池取出顶部或者底部实体 func dequeueSupplementaryView (_ viewClass: T.Type, kind: String, indexPath: IndexPath) -> T { let identifier = viewClass.className if let cell = dequeueReusableSupplementaryView(ofKind: kind, withReuseIdentifier: identifier, for: indexPath) as? T { return cell } else { return T() } } /// 滑动到第一个 Cell 位置，通过增加判断，防止奔溃 func scrollToFirstCell(animated: Bool = true) { guard self.numberOfSections > 0 else { return } guard let count = self.dataSource?.collectionView(self, numberOfItemsInSection: 0) else { return } if count > 0 { if let flowLayout = self.collectionViewLayout as? UICollectionViewFlowLayout { if flowLayout.scrollDirection == .horizontal { scrollToItem(at: IndexPath(row: 0, section: 0), at: .left, animated: animated) } else { scrollToItem(at: IndexPath(row: 0, section: 0), at: .top, animated: animated) } } } }}复制代码 Array+Convenience
功能：数组便捷操作，其中 safeIndex 是为了防止数组越界，双边遍历的需求是为了优化显示图片列表加载，从用户当前看到的图片开始向两边加载
extension Array { /// 获取数组中的元素，增加了数组越界的判断 func safeIndex(_ i: Int) -> Array.Iterator.Element? { guard !isEmpty && self.count > abs(i) else { return nil } for item in self.enumerated() { if item.offset == I { return item.element } } return nil } /// 从前面取 N 个数组元素 func limit(_ limitCount: Int) -> [Array.Iterator.Element] { let maxCount = self.count var resultCount: Int = limitCount if maxCount < limitCount { resultCount = maxCount } if resultCount <= 0 { return [] } return self[0.. [Array.Iterator.Element] { var items = self while items.count > 0 && items.count < fullCount { items = (items + items).limit(fullCount) } return items.limit(fullCount) } /// 双边遍历，从中间向两边进行遍历 func bilateralEnumerated(_ beginIndex: Int, handler: (Int, Array.Iterator.Element) -> Void) { let arrayCount: Int = self.count var leftIndex: Int = Swift.max(0, Swift.min(beginIndex, arrayCount - 1)) var rightIndex: Int = leftIndex + 1 var currentIndex: Int = leftIndex var isLeftEnable: Bool = leftIndex >= 0 && leftIndex < arrayCount var isRightEnable: Bool = rightIndex >= 0 && rightIndex < arrayCount var isLeft: Bool = isLeftEnable ? true : isRightEnable while isLeftEnable || isRightEnable { currentIndex = isLeft ? leftIndex : rightIndex if let element = self.safeIndex(currentIndex) { handler(currentIndex, element) } if isLeft { leftIndex -= 1 } else { rightIndex += 1 } isLeftEnable = leftIndex >= 0 && leftIndex < arrayCount isRightEnable = rightIndex >= 0 && rightIndex < arrayCount if isLeftEnable && !isRightEnable { isLeft = true } else if !isLeftEnable && isRightEnable { isLeft = false } else if isLeftEnable && isRightEnable { isLeft = !isLeft } } }}复制代码 NSDictionary+Convenience
功能：简化从字典中取值的代码，并支持多键查找
extension NSDictionary { // MARK: - 以下都是从字典里取值的快捷方法，支持多键查找和默认返回 func bool(_ keys: String..., defaultValue: Bool = false) -> Bool { return valueForKeys(keys, type: Bool.self) ?? defaultValue } func double(_ keys: String..., defaultValue: Double = 0.0) -> Double { return valueForKeys(keys, type: Double.self) ?? defaultValue } func int(_ keys: String..., defaultValue: Int = 0) -> Int { return valueForKeys(keys, type: Int.self) ?? defaultValue } func string(_ keys: String..., defaultValue: String? = nil) -> String? { return valueForKeys(keys, type: String.self) ?? defaultValue } func dictionary(_ keys: String..., defaultValue: NSDictionary? = nil) -> NSDictionary? { return valueForKeys(keys, type: NSDictionary.self) ?? defaultValue } func array (_ keys: String..., type: T.Type, defaultValue: [T] = []) -> [T] { return valueForKeys(keys, type: Array .self) ?? defaultValue } // MARK: - 以下是从字典里取值的核心方法，支持多键查找 fileprivate func valueForKeys (_ keys: [String], type: T.Type) -> T? { for key in keys { if let result = self[key] as? T { return result } } return nil }}复制代码 Demo 源代码在这：
这些分类方法都是我在项目中比较常用的，能简化很多代码，希望你们喜欢！O(∩_∩)O哈哈~