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如何更新绑定到windowsforms.textbox.datasource的。嗯…每个textChanged事件的数据源(键入期间)?

textbox data-binding winforms .net

1

Roman Pokrovskij Archil Labadze · 技术社区 · 15 年前

如果您想在键入时更新一些“计数器”或“错误状态”,这很有用。

有时我以前用过这个代码,但它看起来太复杂了。可能还有其他更简单的解决方案吗?

class FlashTextBox:TextBox
{
  protected override void OnTextChanged(EventArgs e)
  {
   Binding binding = this.DataBindings["Text"];
   if (binding!=null)
   {
    PropertyManager propertyManager = 
                                binding.BindingManagerBase as PropertyManager;
    if (propertyManager!=null)
    {
               PropertyInfo pinfo =      
                                    binding.DataSource.GetType()
                                    .GetProperty(binding.BindingMemberInfo.BindingField,
                                    BindingFlags.Instance | BindingFlags.Public);
     pinfo.SetValue(binding.DataSource, this.Text, null);
    } 
   }
                    if (isAutoScrollVisible)
                    {
                            ChangeScrollVisibility();
                    }
   base.OnTextChanged (e);
  }

  const int WM_KEYDOWN = 0x0100;
  public override bool PreProcessMessage(ref System.Windows.Forms.Message msg)
  {
   if(msg.Msg == WM_KEYDOWN)
   {
    switch((Int32)msg.WParam)
    {
     case (int)Keys.Enter :
      if (EnterPressed!=null)
       EnterPressed(this,EventArgs.Empty);
      break;
    }
   } 
   return base.PreProcessMessage(ref msg);
  }
}

1 回复 | 直到 13 年前

1

3

Ryan Lundy 13 年前

下面的代码段显示如何将textbox.text属性绑定到业务对象的propertyname属性。确保将DataSourceUpdateMode.OnPropertyChanged设置设置为DataSourceUpdateMode.OnValidation是文本框控件的默认设置。

var bindingSource = new System.Windows.Forms.BindingSource();
bindingSource.DataSource = businessObject;
flashTextBox.DataBindings.Add(new System.Windows.Forms.Binding(
    "Text", 
    bindingSource, 
    "PropertyName", 
    true, 
    System.Windows.Forms.DataSourceUpdateMode.OnPropertyChanged
    ));

有关更多详细信息,请参阅msdn文档: http://msdn.microsoft.com/en-us/library/system.windows.forms.binding.aspx