网络表单中的构造函数?

Constructor in webform?(网络表单中的构造函数?)

问题描述

我有一个 ASP.NET 网络表单，我在其中使用页面上的控件列表初始化一个数组，如下所示

I have an ASP.NET webform where I initialize an array with a list of controls on the page like this

FileUpload[4] = new FileUpload[4];
public myclass()
{
 fileUpload[0] = FileUpload1;
 fileUpload[0] = FileUpload2;
...etc
}

然后我在页面加载中使用这些，它们都为空.这对我来说似乎是一种奇怪的行为.有人可以详细说明和解释吗?我可以理解它们在构造函数中为空，但为什么在页面加载中使用时它们应该为空.

I then use these in the page load and they are all null. This seems a strange behavior to me. Can someone elaborate and explain? I can understand that they are null in the constructor but why should they be null when used in the page load.

推荐答案

它们为空，因为尚未创建控件.

They are null because the controls haven't been created yet.

查看 ASP.NET 页面生命周期概述 和 Init 事件.

Take a look at the ASP.NET Page Life Cycle Overview and the Init event.

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