下划线模板投掷变量未定义错误

I've watched some videos on the topic of backbone js. This is an example straight from the video. It is from 2012, so I'm thinking backbone rules/library have changed, but I can't figure out why this does not work at the moment. In the video, the person shows it running in the JS Fiddle, but I can't get it to work. (I've included the necessary libraries in JS Fiddle, i.e. underscore, backbone and jQuery)

我看过一些关于骨干js主题的视频。这是直接来自视频的示例。它是从2012年开始的,所以我认为骨干规则/库已经发生了变化,但我无法弄清楚为什么它现在不起作用。在视频中,该人显示它在JS Fiddle中运行,但我无法让它工作。 (我在JS Fiddle中包含了必要的库,即下划线,主干和jQuery)

var V = Backbone.View.extend({  el:'body',  render: function () {  	var data = { lat: -27, lon: 153 };    this.$el.html(_.template('<%= lat %> <%= lon%>', data));    return this;  }});var v = new V();v.render();

<script src="http://underscorejs.org/underscore-min.js"></script><script src="https://ajax.googleapis.com/ajax/libs/jquery/1.11.1/jquery.min.js"></script><script src="http://backbonejs.org/backbone-min.js"></script>

2 个解决方案

#1

You used to be able to parse and fill in an Underscore template in one go like this:

您以前可以像这样一次解析并填写下划线模板:

var html = _.template(template_string, data);

But as of Underscore 1.7.0, the second argument to _.template contains template options:

但是从Underscore 1.7.0开始,_.template的第二个参数包含模板选项:

template _.template(templateString, [settings])

template _.template(templateString,[settings])

Compiles JavaScript templates into functions that can be evaluated for rendering. [...] The settings argument should be a hash containing any _.templateSettings that should be overridden.

将JavaScript模板编译为可以评估渲染的函数。 [...] settings参数应该是一个包含任何应该被覆盖的_.templateSettings的哈希。

You have to compile the template using _.template and then execute the returned function to get your filled in template:

您必须使用_.template编译模板,然后执行返回的函数以获取填充的模板:

var tmpl = _.template(template_string);var html = tmpl(data);// or as a one-liner, note where all the parentheses arevar html = _.template(template_string)(data);

In your case, it would look something like this:

在你的情况下,它看起来像这样:

var V = Backbone.View.extend({  el:'body',  render: function () {    var data = { lat: -27, lon: 153 };    var tmpl = _.template('<%= lat %> <%= lon %>');    this.$el.html(tmpl(data));    return this;  }});var v = new V();v.render();

<script src="//cdnjs.cloudflare.com/ajax/libs/underscore.js/1.8.3/underscore-min.js"></script><script src="//ajax.googleapis.com/ajax/libs/jquery/1.11.1/jquery.min.js"></script><script src="//cdnjs.cloudflare.com/ajax/libs/backbone.js/1.1.0/backbone-min.js"></script>

#2

This can be useful

这可能很有用

1: If you have more then one template or sometime you are using external template so it can be useful for you inside method you can write reusable code

1:如果你有一个以上的模板或者某个时候你正在使用外部模板,所以它对你内部方法很有用,你可以编写可重用的代码

var V = Backbone.View.extend({    el:'body',    temp: function (str) {        // reusable code        return _.template(str);    },    render: function () {        var data = { lat: -27, lon: 153 };        // calling your view method temp                var tmpl = this.temp('<%= lat %> <%= lon %>');        this.$el.html(tmpl(data));        return this;    }});var v = new V();v.render();

#1