一个什么是一个视图内的变量的范围有多大？ [英] What is a the scope of a variables inside a view?

问题描述

如果我有code，看起来像这样一个ASP.NET MVC视图中：

If I have code inside an ASP.NET MVC view that looks like this:

<%
    bool admin = false;
    if (ViewData.ContainsKey("isAdmin"))
    {
        admin = (bool)ViewData["isAdmin"];
    }
    if (admin)
    {
%>
<%--
    ... generate table of html
--%>

和后来在页面创建在另一个code另一个脚本渲染块＆LT;％％＆GT; ，我可以重复使用管理员变量，将其从网页需要更高的记忆状态，或者是范围只是在＆LT;％％＆GT; 块

and later down the page I create another script inside another code render block <% %>, can I reuse the admin variable and will it remember the state from higher in the page, or is the scope just inside the <% %> blocks?

推荐答案

变量通常在一个视图范围，但它可以得到标签混淆。认为整个视图与标签（和标签本身）为空白之外的一切的单一方法。在视图中块之外定义的变量将范围限定为整个视图。一个块中定义的变量（foreach循环/如果再把/使用）将作用域该块。你不能重复使用具有pviously被外块定义$ P $一个块中的一个变量。

Variables are scoped normally in a view, though it can get confusing with the tags. Think of the whole view as a single method with everything outside the tags (and the tags themselves) as whitespace. A variable defined outside a block in the view will be scoped to the entire view. A variable defined inside a block (foreach loop/if then/using) will be scoped to that block. You can't reuse a variable inside a block that has previously been defined outside the block.

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