如何仅从 TextBox 获取新文本？

Question

private void tbLog_TextChanged(object sender, TextChangedEventArgs e)
{
    //Get only NEW text added to Log
}

/*
    LOG
    old message...
    old message...
    old message...
    old message...
    NEW message...
    NEW message...
    NEW message...
    NEW message...
    NEW message...
*/  

如何仅从 TextBox 获取新文本？

Answer 1

也许您应该使用该TextChangedEventArgs.Changes属性：

var fullText = tbLog.Text;
if (e.Changes.Any())
{
    var additions = e.Changes.Where(tc => tc.AddedLength > 0);
    var newTexts = additions.Select(tc => fullText.Substring(tc.Offset, tc.AddedLength));

    // TODO: Do stuff with the new pieces of text
}