正如你已经说 chrome.tabs.query 函数是异步的。正因为如此，你不能依靠收益，相反，你必须使用回调。对于Chrome扩展的文档解释了它相当不错： http://developer.chrome.com /extensions/overview.html#sync-example

As you already said the chrome.tabs.query function is asynchronous. Because of this, you cannot rely on return, instead you have to use callbacks. The documentation for Chrome extension explains it quite well: http://developer.chrome.com/extensions/overview.html#sync-example

所以你的情况，这样的事情可能工作（取决于你想以后做什么用）。

So in your case, something like this might work (depends on what you want to later with it).

var url, tab;
function init(){
    chrome.tabs.query({currentWindow: true, active: true},function(tabs){
       url = tabs[0].url;
       tab = tabs[0];
       //Now that we have the data we can proceed and do something with it
       processTab();
    });
}

function processTab(){
    // Use url & tab as you like
    console.log(url);
    console.log(tab);
}