在c＃中调用两次构造函数 [英] call contructor twice in c#

问题描述

我写了一个程序就像记事本一样有胜利形式。



我想打开一些txt文件，并显示它们。



我有一个名为DirtyCheckingTextBox的类，它派生自TextBox，

我在表单中使用DirtyCheckingTextBox tbxContent来显示文本。


openMenu点击事件中的
：

I wrote a program works like the notepad with win form.

I want to open some txt file, and display them.

I have a class called DirtyCheckingTextBox which derived from TextBox,
I use the DirtyCheckingTextBox tbxContent in the form to display text.

in the openMenu click event :

{
  // .. openfiledialog stuff
  var content = FileServices.GetContent(fileName); // get the txt content
  tbxContent = new DirtyCheckingTextbox(content);
}

构造函数：

the Constructor:

 public DirtyCheckingTextbox() : this(String.Empty)
 {
 }

public DirtyCheckingTextbox(string initialText)
{
    this.Text = initialText;
    this.CleanText = this.Text;
}

但问题是我发现调试窗口tbxContent.Text有txt文件内容，但表单不显示文本，为什么？



默认情况下tbxContent调用默认构造函数，我想问题可能是我再次调用构造函数新的DirtyCheckingTextbox（内容）;

but the problem is that I found the the debug window the tbxContent.Text has the txt files content, but the form doesn't display the text, why?

by default the tbxContent call the default constructor, I think the problem maybe I call the constructor again new DirtyCheckingTextbox(content);

推荐答案

正如RyanDev所说，需要将testbox添加到表单中。

As RyanDev said the testbox needs to be added to the form.

TextBox DirtyCheckingTextbox= new TextBox();
DirtyCheckingTextbox.Location = new Point(200, 200);
this.Controls.Add(DirtyCheckingTextbox);
DirtyCheckingTextbox.Text = content ;

祝你好运。

Good luck.

问题是你正在创建一个新的DirtyCheckingTextbox的实例并将其分配给tbxContent变量 - 它不显示它，或者更新已经在显示器上的版本。



相反，移动你的将代码编入方法，并调用：

The problem is that you are creating a new instance of the DirtyCheckingTextbox and assigning it to the tbxContent variable - which doesn't display it, or update the version which is already on the display.

Instead, move your code into a method, and call that:

public DirtyCheckingTextbox() : this(String.Empty)
    {
    }
    
public DirtyCheckingTextbox(string initialText)
    {
    Reset(initialText);
    }

public void Reset(string initialText)
    this.Text = initialText;
    this.CleanText = this.Text;
    }

{
// .. openfiledialog stuff
var content = FileServices.GetContent(fileName); // get the txt content
tbxContent.Reset(content);
}

类型 - 非常奇怪的拼写错误 - OriginalGriff [/ edit]

[edit]Types - very odd typos - OriginalGriff[/edit]

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