调用函数中定义的函数 [英] Calling a function that's defined inside a function

问题描述

*有没有办法在javaSCRIPT中的另一个函数中调用函数定义？例如：
$ b $ pre $ window.onload（）= function（）{
函数my_function（）{
打印（ 等等）;
};
};

function function_two（）{
my_function（）;
};


有没有办法像上面那样做（在function_two中调用my_function，即使它是在window.onload（）函数）？在我使用raphael.js库的实际代码中，我试图在HTML中编写一个使用onClick函数的按钮，调用一个函数（如function_two），它运行window.onload（）中定义的函数（）（像my_function）。但是控制台说my_function是未定义的。

解决方案

Zeychin和Trevor说过，函数的范围是核心问题。我想我会提供另一种处理方式。基本上，您可以将函数设置为一个更高范围的变量（即onload和function_two函数都可以访问），同时在onload函数中定义它，就像您最初的那样：

  var myFunction; //这是设置范围
 
的占位符window.onload（）= function（）{
 myFunction = function（）{//将函数赋值给myFunction变量
 print（'blah'）; 
 
 
 
 function function_two（）{
 myFunction（）; 
 
 
 
 $ b $ p 
 $ b 
如果你只知道myFunction所需的信息， '在onload事件中。
 
*Is there a way to call a function defined inside another function in javaSCRIPT? For example:
window.onload() = function() {
    function my_function(){
        print("Blah");
    };
};

function function_two(){
    my_function();
};
Is there a way to do something like the above (calling my_function in function_two even though it's defined inside the window.onload() function)? In my actual code, which also uses the raphael.js library, I'm trying to write a button in HTML, which using the onClick function, calls a function(like function_two) that runs the function defined in window.onload() (like my_function). However the console says that the my_function is undefined. 
解决方案
The scope of the function is the core issue here, as Zeychin and Trevor have said. I thought I'd offer another way of handling it. Basically, you can set your function to a variable that's in a higher scope (that is, accessible to both the onload and function_two functions), while defining it inside the onload function as you originally have:
var myFunction; //This is the placeholder which sets the scope

window.onload() = function() {
   myFunction = function() { //Assign the function to the myFunction variable
      print('blah');
   }
}

function function_two() {
   myFunction();
}
This might be handy if you only know the information you need for myFunction once you're in the onload event.

                        
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