确定何时以及哪些字符添加或在文本框中删除 [英] Determine when and which character is added or deleted in a Text Box

问题描述

我有一个WPF应用程序一个简单的文本框。

I have a simple text box in a WPF application.

我需要知道的在加入一个字符/文本中删除中，这字符和其中，它被添加或删除。

I need to know when a character was added/deleted in the text box, which character and where it was added or deleted.

我想过使用 TextBox.KeyDown 事件，但它也存在一些问题：

I thought about using the TextBox.KeyDown event, but it has some problems:

• 我不知道在哪里添加或删除角色。


• 我不知道如何确定哪些角色是增加（从 KeyEventArgs ）。

• I can't know where the character was added or deleted.
• I have no idea how to determine which character was added (from the KeyEventArgs).

任何想法？

推荐答案

找到了解决办法。在WPF中， TextBox.TextChanged 事件有一个 TextChangedEventArgs 。在这个类中，有一个名为更改属性

Found the solution. In WPF, the TextBox.TextChanged event has a TextChangedEventArgs. In this class, there is a property named Changes.

下面是我的代码：

private void textBox1_TextChanged(object sender, TextChangedEventArgs e)
{
    foreach (var change in e.Changes)
    {
        if (change.AddedLength > 0 && change.RemovedLength == 0)
        {
            if (change.AddedLength == 1)
            {
                AddCharacter(textBox1.Text[change.Offset], change.Offset);
            }
            else
            {
                AddString(textBox1.Text.Substring(change.Offset, change.AddedLength), change.Offset);  
            }
        }
        else if (change.AddedLength == 0 && change.RemovedLength > 0)
        {
            if (change.RemovedLength == 1)
            {
                RemoveCharacter(change.Offset);
            }
            else
            {
                RemoveString(change.Offset, change.RemovedLength + change.Offset);
            }
        }
        else if (change.AddedLength == 1 & change.RemovedLength == 1)
        {
            ReplaceCharacter(change.Offset, textBox1.Text[change.Offset]);
        }
        else
        {
            ReplaceString(change.Offset, change.Offset + change.RemovedLength, textBox1.Text.Substring(change.Offset, change.AddedLength));
        }
    }
}

现在我只需要等待两天接受这个答案。 ：）

Now I just need to wait two days to accept this answer. :)

不管怎样，谢谢

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