# 局部

¥Partials

Handlebars 允许通过部分模板重用。Partials 是普通的 Handlebars 模板，可以被其他模板直接调用。

¥Handlebars allows for template reuse through partials. Partials are normal Handlebars templates that may be called directly by other templates.

# 基本局部

¥Basic Partials

为了使用部分，必须通过 Handlebars.registerPartial 注册。

¥In order to use a partial, it must be registered via Handlebars.registerPartial.

preparationScript

Handlebars.registerPartial('myPartial', '{{prefix}}');

此调用将注册 myPartial 部分。部分可以被预编译，并将预编译模板传递到第二个参数中。

¥This call will register the myPartial partial. Partials may be precompiled and the precompiled template passed into the second parameter.

调用部分是通过部分调用语法完成的：

¥Calling the partial is done through the partial call syntax:

template

{{> myPartial }}

将渲染名为 myPartial 的部分。当部分执行时，它将在当前执行上下文下运行。

¥Will render the partial named myPartial. When the partial executes, it will be run under the current execution context.

# 动态局部

¥Dynamic Partials

可以使用子表达式语法动态选择要执行的部分。

¥It's possible to dynamically select the partial to be executed by using sub expression syntax.

template

{{> (whichPartial) }}

将评估 whichPartial，然后渲染该函数返回名称的部分。

¥Will evaluate whichPartial and then render the partial whose name is returned by this function.

子表达式不解析变量，因此 whichPartial 必须是一个函数。如果一个简单变量具有部分名称，则可以通过 lookup 辅助程序来解析它。

¥Subexpressions do not resolve variables so whichPartial must be a function. If a simple variable has the partial name, it's possible to resolve it via the lookup helper.

template

{{> (lookup . 'myVariable') }}

# 局部上下文

¥Partial Contexts

通过将上下文传递给部分调用，可以在自定义上下文上执行部分。

¥It's possible to execute partials on a custom context by passing in the context to the partial call.

template

{{> myPartial myOtherContext }}

# 局部参数

¥Partial Parameters

自定义数据可以通过哈希参数传递给部分。

¥Custom data can be passed to partials through hash parameters.

template

{{> myPartial parameter=favoriteNumber }}

部分运行时将参数设置为 value。

¥Will set parameter to value when the partial runs.

这对于将父上下文中的数据公开给部分上下文特别有用：

¥This is particularly useful for exposing data from parent contexts to the partial:

template

{{#each people}}
  {{> myPartial prefix=../prefix firstname=firstname lastname=lastname}}.
{{/each}}

# 局部块

¥Partial Blocks

尝试渲染未找到的部分时的正常行为是实现抛出错误。如果需要故障转移，则可以使用块语法调用部分。

¥The normal behavior when attempting to render a partial that is not found is for the implementation to throw an error. If failover is desired instead, partials may be called using the block syntax.

template

{{#> myPartial }}
  Failover content
{{/myPartial}}

如果 myPartial 部分未注册，则将渲染 Failover content。

¥Which will render Failover content if the myPartial partial is not registered.

此块语法还可用于将模板传递给部分，该部分可以由专门命名的部分 @partial-block 执行。一个模板

¥This block syntax may also be used to pass templates to the partial, which can be executed by the specially named partial, @partial-block. A template of

template

{{#> layout }}
My Content
{{/layout}}

layout 部分包含

¥with the layout partial containing

partial: layout

Site Content {{> @partial-block }}

会渲染

¥Would render

output

Site Content My Content

当以这种方式调用时，该块将在调用时的部分上下文中执行。深度路径和块参数相对于部分块而不是部分模板进行操作。

¥When called in this manner, the block will execute under the context of the partial at the time of the call. Depthed paths and block parameters operate relative to the partial block rather than the partial template.

template

{{#each people as |person|}}
  {{#> childEntry}}
    {{person.firstname}}
  {{/childEntry}}
{{/each}}

将从该模板渲染 person.firstname，而不是部分渲染。

¥Will render person.firstname from this template, not the partial.

# 内嵌局部

¥Inline Partials

模板可以通过 inline 装饰器定义块作用域的部分。

¥Templates may define block scoped partials via the inline decorator.

template

{{#*inline "myPartial"}}
  My Content
{{/inline}}
{{#each people}}
  {{> myPartial}}
{{/each}}

这将为每个子级渲染 myPartial 部分。

¥Which will render the myPartial partial for each child.

每个内联部分可用于当前块和所有子块，包括其他部分的执行。这允许布局模板和类似的功能：

¥Each inline partial is available to the current block and all children, including execution of other partials. This allows for layout templates and similar functionality:

template

{{#> layout}}
  {{#*inline "nav"}}
    My Nav
  {{/inline}}
  {{#*inline "content"}}
    My Content
  {{/inline}}
{{/layout}}

其中 layout 部分可能是：

¥Where the layout partial may be:

partial: layout

<div class="nav">
  {{> nav}}
</div>
<div class="content">
  {{> content}}
</div>

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