Javascript OOP从函数返回值

本文介绍了Javascript OOP从函数返回值的处理方法，对大家解决问题具有一定的参考价值，需要的朋友们下面随着小编来一起学习吧！ 问题描述

function SocialMiner（） { var verbose = true; var profileArray = new Array（）; var tabUrl; this.getTabUrl = function（） { logToConsole（getTabUrl is called）; chrome.tabs.getSelected（null，function（tab） { tabUrl = tab.url; logToConsole（tabUrl）; }）; 返回tabUrl; }`

然后我在SocialMiner ojbect上调用这个函数：

var pageUrl = miner.getTabUrl（）; miner.logToConsole（pageUrl）;

第一次调用 logToConsole 成功打印Url，而第二个说未定义。我是不是从函数返回相同的值？

更新：这是我如何定义logToConsole：

<$ （文本） { if（verbose） console.log（text）; pre $ } this.logToConsole = logToConsole;

解决方案

在第二个示例中，您正在调用logToConsole，它是矿工对象的一个​​功能，不是。

miner.logToConsole this.logToConsole = function（text） { if（verbose） console.log（text）; }

I have javascript object defined like this:

function SocialMiner() { var verbose=true; var profileArray=new Array(); var tabUrl; this.getTabUrl=function() { logToConsole("getTabUrl is called"); chrome.tabs.getSelected(null, function(tab) { tabUrl = tab.url; logToConsole(tabUrl); }); return tabUrl; } `

Then I call this function on SocialMiner ojbect like this:

var pageUrl=miner.getTabUrl(); miner.logToConsole(pageUrl);

What is the reason that first call to logToConsole successfully prints the Url, while second one says undefined. Am I not returning the same value from the function ?

Update: This is how I have defined logToConsole:

function logToConsole(text) { if (verbose) console.log(text); } this.logToConsole=logToConsole;

解决方案

In the second example, you are calling logToConsole as if it is a function of the miner object, which is is not.

miner.logToConsole

Edit

Per comments about github example, this should make the logToConsole function par of the SocialMiner object. However, I didn't read the class thoroughly, so proceed with caution with regards to how it is intended to be used.

this.logToConsole=function(text) { if (verbose) console.log(text); }