城市代码 获取 Emoij ， 字符串 拼音 处理

String+Country.swift

//
//  String+Country.swift
//  Rate
//
//  Created by 0x30 on 2017/11/20.
//  Copyright © 2017年 s. All rights reserved.
//

import Foundation

extension String{
    
    
    /// 根据 城市Code 获取 Emoij 表情
    ///
    /// - Parameter country: 国家代码
    /// - Returns: 城市Emoij 表情字符串
    static func flag(country:String) -> String {
        let base : UInt32 = 127397
        var s = ""
        for v in country.unicodeScalars {
            s.unicodeScalars.append(UnicodeScalar(base + v.value)!)
        }
        return String(s)
    }
    
    
    /// 去掉字符串的前后字符串
    ///
    /// - Returns: 处理后的字符串
    func trim() -> String {
        
        return self.trimmingCharacters(in: .whitespacesAndNewlines)
    }
    
    
    /// 将中文 转换为 拼音字符串
    ///
    /// - Returns: 拼音字符串
    func toPinYin() -> String{
        
        let string = CFStringCreateMutableCopy(nil, 0, self as CFString);
        CFStringTransform(string, nil, kCFStringTransformMandarinLatin, false);
        CFStringTransform(string, nil, kCFStringTransformStripDiacritics, false);
        
        if let str = string as String?{
            
            return str.replacingOccurrences(of: " ", with: "")
        }
        
        return self
    }
}