node.js - Handlebarsjs 留下的表情

Question

我正在寻找一种解决方案，如何使用 Handlebarsjs 编译 HTML 模板而不忽略未填充的数据。

例如:

var Handlebars = require("handlebars");
var html = "<div>{{foo}}</div><div>{{foo2}}</div>";
html = Handlebars.compile(html)({
    foo : "This is a sample"
});
console.log(html);

是否有可用的编译选项可以帮助我留下表达式？像这样:

html = Handlebars.compile(html)({
   foo : "This is a sample"
},{isLeftBehindEx:true});
<div>This is a sample</div><div>{{foot2}}</div>

Answer 1

1. Expressions are helpers

   This expression means "look up the title property in the current context". [...]
   Actually, it means "look for a helper named title, then do the above" [...]

2. 当助手丢失时，internal helper named helperMissing被调用来替换缺失的表达式

3. 您可以通过pass an options hash when you execute your template提供自定义帮助程序。

有了这些知识，您就可以用任意字符串表示形式替换缺失值:

var compiled = Handlebars.compile(html);
html = compiled({
    foo : "This is a sample"
}, {
    helpers: {
        helperMissing: function(o) {
            return '{{' + o.name + '}}';
        }
    }
});

还有一个演示 http://jsfiddle.net/jrtrvmd4/

或者，如果您愿意，也可以全局覆盖 helperMissing ，并将其输出限制在作为 data 选项传递的可选标志上，例如 isLeftBehindEx按照您的建议:

Handlebars.registerHelper('helperMissing', function(o) {
    return (o.data.isLeftBehindEx) ? '{{' + o.name + '}}' : "";
});

html = compiled({
    foo : "This is a sample"
}, {
    data: {
        isLeftBehindEx: true
    }
});

http://jsfiddle.net/jrtrvmd4/3/