1

我有一个 Meteor Handlebars 模板助手，它代表了我的大多数模板助手，如下所示。

# Address Form Controls Template
Template.AddressFormControls.helpers
    address1: () ->
        if typeof Session.get('edit-building') is 'string'
            building = Buildings.findOne(Session.get('edit-building'))
            return building?.address?.address1

    address2: () ->
        if typeof Session.get('edit-building') is 'string'
            building = Buildings.findOne(Session.get('edit-building'))
            return building.address.address2

    city: () ->
        if typeof Session.get('edit-building') is 'string'
            building = Buildings.findOne(Session.get('edit-building'))
            return building.address.city

    state: () ->
        if typeof Session.get('edit-building') is 'string'
            building = Buildings.findOne(Session.get('edit-building'))
            return building.address.state

    zip_code: () ->
        if typeof Session.get('edit-building') is 'string'
            building = Buildings.findOne(Session.get('edit-building'))
            return building.address.zip_code

    main: () ->
        if typeof Session.get('edit-building') is 'string'
            building = Buildings.findOne(Session.get('edit-building'))
            return building?.phone?.main

    fax: () ->
        if typeof Session.get('edit-building') is 'string'
            building = Buildings.findOne(Session.get('edit-building'))
            return building?.phone?.fax

您会注意到每个帮助程序都包含一个if语句来查看 Session 变量是否为字符串。如果它是一个字符串，那么它应该是一个可用于执行所需对象搜索的 ID。

对于一个人使用的各种收藏品，在整个项目中重复这一点似乎是一种浪费。

我怎样才能把它弄干？

帮助我欧比旺，你是我唯一的希望！

4

1 回答 1

1

你可以用类似的东西来缩短它

js：

main:function() {
    building = Buildings.findOne({_id:Session.get('edit-building')}) 
    return building && building.phone && building.phone.main;
}

咖啡：

main: () ->
    building = Buildings.findOne(_id: Session.get("edit-building"))
    building and building.phone and building.phone.main

关键区别在于明确表示您希望_id匹配。因此，如果Session变量 foredit-building不存在、不是字符串或不匹配任何记录，则不会返回任何内容。

这也可能会大大缩短您的代码：

building: () ->
    Buildings.findOne(_id: Session.get("edit-building"))

然后在您的 html 中（在 AddressFormControls 模板中），您可以执行以下操作：

{{#if building}}
    Phone: {{building.phone.main}}
    Fax: {{building.phone.fax}}
    ....
{{/if}}
于 2013-08-06T16:10:43.723 回答