添加系统版本获取逻辑

MRFramework/MRFramework/FoundationManagers/DeviceInfo/MRDevice.swift

@@ -9,6 +9,58 @@
 import Foundation
 import KeychainAccess
 
+/// 系统版本号封装
+public struct MRSystemVersion {
+    
+    private var version: String
+    
+    public var string: String {
+        return version
+    }
+    
+    init(version: String) {
+        self.version = version
+    }
+}
+
+extension MRSystemVersion: Equatable {
+    public static func == (lhs: MRSystemVersion, rhs: MRSystemVersion) -> Bool {
+        return lhs.version == rhs.version
+    }
+}
+
+extension MRSystemVersion: MRCompareToString {
+    public static func == (lhs: MRSystemVersion, rhs: String) -> Bool {
+        return lhs.version == rhs
+    }
+    
+    public static func < (lhs: MRSystemVersion, rhs: MRSystemVersion) -> Bool {
+        return lhs.compare(with: rhs.version) == .orderedSame
+    }
+    
+    public static func >= (lhs: MRSystemVersion, rhs: String) -> Bool {
+        let rs = lhs.compare(with: rhs)
+        return rs == .orderedSame || rs == .orderedDescending
+    }
+    
+    public static func > (lhs: MRSystemVersion, rhs: String) -> Bool {
+        return lhs.compare(with: rhs) == .orderedDescending
+    }
+    
+    public static func <= (lhs: MRSystemVersion, rhs: String) -> Bool {
+        let rs = lhs.compare(with: rhs)
+        return rs == .orderedSame || rs == .orderedAscending
+    }
+    
+    public static func < (lhs: MRSystemVersion, rhs: String) -> Bool {
+        return lhs.compare(with: rhs) == .orderedAscending
+    }
+    
+    public func compare(with string: String) -> ComparisonResult {
+        return self.version.compare(string)
+    }
+}
+
 /// 设备信息
 public final class MRDevice {
     
@@ -19,6 +71,11 @@ public final class MRDevice {
         return UIDevice.current.modelVersion
     }
     
+    /// 系统版本号
+    public class var systemVersion: MRSystemVersion {
+        return MRSystemVersion(version: UIDevice.current.systemVersion)
+    }
+    
     /// App的版本号
     public class var appShortVersion: String? {
         return Bundle.main.infoDictionary?["CFBundleShortVersionString"] as? String