UIImage保存到沙盒

// 获取图片
let uploadImage = UIImage(named: "jiadai");

// 保存文件的名称
let paths = NSSearchPathForDirectoriesInDomains(.DesktopDirectory, .AllDomainsMask, true);

/*
前面参数
DesktopDirectory
DocumentDirectory
DocumentationDirectory
*/

/*
后面参数
UserDomainMask 保存在沙盒根目录
AllDomainsMask 保存在沙盒的Library路径下
*/

let filePath = paths[0] + "jiadai.png";

print("\(filePath)");

// 保存成功会返回true
let result = UIImagePNGRepresentation(uploadImage!)?.writeToFile(filePath, atomically: true);

print("\(result)");