Python Decorator Initial Learning

The first step simple function

1 " " simple function: Call two times " " 2 def myfunc (): 3     Print ('myfunc () called. ' )45myfunc ()6 myfunc ()

The second step adorner provides additional functionality for the calling function

1 " "Replace function (decoration)2 The parameter of the adornment function is the decorated function object, returning the original function object3 The material statement of the ornament; myfunc = Deco (myfunc)" "4 defDeco (func):5     Print("before MyFunc () called.")6 func ()7     Print("After MyFunc () called.")8     returnfunc9 Ten defmyfunc (): One     Print("MyFunc () called.") A  -MyFunc =deco (MyFunc) - MyFunc () theMyFunc ()

The third step uses the syntax @ to decorate the function

1 " "use the syntax @ to decorate the function, equivalent to MyFunc = Deco (myfun)2 but the new function is called only the first time, and the original function calls once more" "3 defDeco (func):4     Print("before MyFunc () called.")5 func ()6     Print("After MyFunc () called.")7     returnfunc8 9 @decoTen defmyfunc (): One     Print("MyFunc () called.") A  - MyFunc () -MyFunc ()

Fourth Step

Python Decorator initial learning