println(ZXKV["homepage"]) //nil        
ZXKV["homepage"] = "http://www.zhangxi.me"  // store a value to the key
println(ZXKV["homepage"]) //http://www.zhangxi.me

let array = ["abc","123"]
ZXKV["array"] = array
println(ZXKV["array"])  //["abc","123"]

//any object which implemented NSCoding can be stored.

ZXKV.prefix("100") //Return Array<(key:String,value:AnyObject)> which key begins with prefix("100")

ZXKV.surfix("zx") //Return Array<(key:String,value:AnyObject)> which key ends with surfix("zx")

ZXKV.glob("*zx")  //Return Array<(key:String,value:AnyObject)> [GLOB](http://www.runoob.com/sqlite/sqlite-glob-clause.html)
ZXKV.like("%zx")  //Return Array<(key:String,value:AnyObject)> [LIKE](http://www.runoob.com/sqlite/sqlite-like-clause.html)


ZXKV.first()  //first inserted object
ZXKV.last()   //last inserted object

println(ZXKV.count("key"))       //0
println(ZXKV.increase("key"))    //1
ZXKV.setCount("key", value: 10)  //10
println(ZXKV.count("key"))       //10
println(ZXKV.decrease("key"))    //9
println(ZXKV.count("key"))       //9

println(ZXKV.switchState("key"))                   // nil
println(ZXKV.switchOn("key"))                      //true,means switch on sucess
println(ZXKV.switchState("key"))                   //true,the state is true
println(ZXKV.switchOff("key"))                     //true,means switch off success
println(ZXKV.switchState("key"))                   //false,means the state is false
println(ZXKV.setSwitchState("key", value: true))   //true,set the state to true,sucess
println(ZXKV.switchState("key"))                   //true,the state is true