问题描述
基本上我有 2 个类，Manifest"和BrowserAction"，如下所示:
Basically I have 2 classes, "Manifest" and "BrowserAction", set out like this:
public class BrowserAction
{
public string default_icon {get; set;}
public string default_title {get; set;}
public string default_popup {get; set;}
}
public class Manifest
{
public BrowserAction browser_action {get; set;}
}
问题是，当我尝试设置 Manifest 类的 browser_action.default_popup 的实例时，如下所示:
The problem is, that when I try to set an instance of the Manifest class' browser_action.default_popup, like this:
public void setManifest()
{
Manifest newManifest = new Manifest();
newManifest.browser_action.default_popup = "popup.html";
}
我得到一个 System.NullReferenceException.我环顾四周，但似乎找不到问题所在.它适用于Manifest"类的其他属性，这些属性只是字符串等.
I get a System.NullReferenceException. I've looked around but I can't seem to find what the problem is. It works fine for other properties of the "Manifest" class that are just strings etc.
如果相关，我的 IDE 是 MonoDevelop 2.4，我的框架是 Mono 2.6.7.
If it's relevant, my IDE is MonoDevelop 2.4, with Mono 2.6.7 for my framework.
推荐答案
在访问该实例的属性之前，您还必须初始化 browser_action.
You'll have to intialize browser_action too before accessing properties on that instance.
newManifest.browser_action= new BrowserAction();
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