什么是回调函数 In computer programming, a callback is a piece of executable code that is passed as an argument to other code, which is expected to call back (execute) the argument at some convenient time[引自 维基百科 callback] 回调函数是一段可执行的代码段,它作为一个参数传递给其他的代码,其作用是
#coding=utf-8 import osdef find_file(arg,dirname,files): #for i in arg: #print i for file in files: file_path=os.path.join(dirname,file) print 'file_path:',file_path if os.path.isfile(file_path) and (arg[0] in file or a
昨天写豆瓣发广播Demo的时候,为了写Demo的简单,就使用了Storyboard,结果执行视图跳转时遇到了这个问题: Warning: Attempt to present <UINavigationController: 0x8d514e0> on <OAuthViewController: 0xa044a60> whose view is not in the window hierarchy! 其功能是OAuthViewController用于用户授权,在获取用户的授权后将
基础 // 判断值是否是指定数据类型 var result = hui.isTargetType("百签软件", "string"); //=>true var result = hui.isTargetType(123, "number"); // =>true var result = hui.isTargetType("false", "boolean"); // =>false /
Javascript中,this是一个非常有用的关键字, this是在运行时基于函数的运行环境绑定的,但是,如果使用的时候不注意,很容易就出错了. ECMAScript Standard对this的定义看起来非常简单: The this keyword evaluates to the value of the ThisBinding of the current execution context. 其中,对于ThisBinding和execution context, ECMAScript