Question

我有这个对象，想要从var scrolled = 10;函数中的init函数访问滚动scrollDown的变量。

我无法访问变量。我怎样才能做到这一点？

// Summary Screen Functions
var summary = {
    init: function() {

        var scrolled = 0;

        $('.page-summary-action a').on('click', summary.continueToSummary);
        $('.scroll-down').on('click', summary.scrollDown);
        $('.scroll-up').on('click', summary.scrollUp);
    },

    scrollDown: function(e) {
        e.preventDefault();
        scrolled = scrolled + 300;

        console.log('clicked');

        $(".data-cards").animate({
            scrollTop:  scrolled
        });
    },

    scrollUp: function(e) {
        e.preventDefault();
        console.log('clicked');

        $(".data-cards").animate({
            scrollTop: 15
        });
    }
};

summary.init();

Answer 1

var scrolled = 0; // Put the variable in an outer scope
var summary = {
    init: function() {
        // access "scrolled"
        scrolled = 0;
    },

    scrollDown: function(e) {
        // access "scrolled"
    },

    scrollUp: function(e) {
        // ...
    }
};

summary.init();

或

var summary = {
    scrolled: 0, // Make it a property of the "summary" object
    init: function() {
        // access "scrolled"
        summary.scrolled = 0;
    },

    scrollDown: function(e) {
        // access "scrolled"
    },

    scrollUp: function(e) {
        // ...
    }
};

summary.init();

Answer 2

根据您的问题，您应该使用this.scrolled而不是var。一个例子是

 var summary = {
    init: function() {
        this.scrolled = 20;
    },

    scrollDown: function(e) {
        console.log(this.scrolled);
    },

    scrollUp: function(e) {
        console.log(this.scrolled);
    }
 };   
 summary.init();
 summary.scrollDown();

为了满足您的好奇心，您应该查看此链接How does the “this” keyword work?和Explanation from MDN

如何在另一个函数jquery中访问变量

2 个答案: