ProcessCmdKey 不通过回车键

Question

发生了一些事情，导致我的代码总是捕获 Enter 键但从不处理它。意思是 all 我的数据输入框、网格控件等都坏了。就像Enter键被关闭了。

我已经尝试完全删除 ProcessCmdKey 例程，但它仍在执行。

我有一段相当冗长的代码处理选项卡式表单上的 enter 键，但它弄乱了其他选项卡，这意味着每当 enter 被按下它会捕获它。

所以，我只是查看它在哪个选项卡上，如果不是正确的选项卡，就忽略它，简单吗？没有。

无论出于何种原因，无论什么，我的表单都不会处理回车键。

我已经回到了最基本的代码：

protected override bool ProcessCmdKey(ref Message msg, Keys keyData)
{
    return base.ProcessCmdKey(ref msg, keyData);
}

根据我的理解，上面应该什么都不做，只需将按下的键传递回去然后处理它。

这适用于除 enter 键之外的所有内容。如果我有一个文本框或任何控件，那么它将接受所有输入，但它完全忽略 enter 键。我也试过 return false; 但还是不行。

我什至尝试完全删除例程，但它仍然坏了。重启VS以防万一。

编辑： OK，下面是我开始 "fix" 事情之前的完整原始代码。这可以正常工作，除了它会阻止 Enter 键在程序的其他地方工作。正如您所想象的那样，最终用户并不十分欣赏。

protected override bool ProcessCmdKey(ref Message msg, Keys keyData)
    {

        if (ActiveControl.Name.ToString() != "order_creation_grid") //ensures that we don't caputre keypresses in the datagrid
        {

            //if (keyData == (Keys.Tab | Keys.Shift)) //tabbing backwards
            //{
            //    if (ActiveControl.Parent.Name.ToString() == "order_con_name_DD")
            //    {
            //        order_con_name_DD.Select();
            //        order_con_name_DD.ShowDropDown();

            //    }
            //}
            if (keyData == Keys.Tab || keyData == Keys.Enter)
            {
                if (ActiveControl.Parent.Name.ToString() == "order_shipper_dd")
                {
                    var test = keyData;
                    //getAllConsignees(); remove
                    get_all_addresses(); //load up the address dd
                    order_address_dd.SelectedIndex = 0;
                    order_address_dd.Select();
                    order_address_dd.Focus();
                    return true;//lets the system know that the control key was handled and not to fire it again
                }
                else if (ActiveControl.Parent.Name.ToString() == "order_address_dd")
                {
                    if (order_address_dd.SelectedIndex != -1)//only do this if there is not a new address in the address chooser ie: found one in database
                    {
                    order_match_dd.Select();
                    order_match_dd.Focus();
                        order_match_dd.ShowDropDown();
                    return true;

                    }
                    else
                    {
                        order_address_eb.Value = order_address_dd.Text;
                        order_consignee_eb.Select();
                        order_consignee_eb.Focus();
                        return true; ;
                    }
                }
                else if (ActiveControl.Name.ToString() == "order_match_dd")
                {
                    if (order_match_dd.SelectedIndex != -1)//fire off when a valid selection is made
                    {
                        //check if it is a new item

                        if (order_match_dd.Text == "1 New")
                        {
                            //blank out the fields and position cursor to Consignee
                            clear_order_fields();

                            order_consignee_eb.Select();
                            order_consignee_eb.Focus();
                        }
                        else //parse the value in the match box useing the seperator | into strings and load up the correct fields
                        {
                            char[] delimiterChars = { '|' };
                            string[] fields = order_match_dd.Text.Split(delimiterChars);

                            clear_order_fields();

                            order_consignee_eb.Value = fields[0].ToString().Trim(); ;
                            order_address_eb.Value = fields[1].ToString().Trim();
                            order_city_eb.Value = fields[2].ToString().Trim();
                            order_state_eb.Value = fields[3].ToString().Trim();
                            order_zip_eb.Value = fields[4].ToString().Trim();
                            //go try and match the driver and facility with this zipcode
                            get_driver_facility();

                            order_BOL_eb.Select();
                            order_BOL_eb.Focus();
                        }
                        return true;
                    }

                }
                else if (ActiveControl.Parent.Name.ToString() == "order_BOL_eb")
                {
                    int custID = Convert.ToInt16(order_shipper_dd.SelectedValue);

                    string testFor = order_BOL_eb.Value.ToString();

                    var lookFor = (from l in dbContext.stop_details
                                   where l.cust_unique_id == testFor && l.customer_id == custID
                                   select l).ToArray();

                    int count = lookFor.Count();
                    if (count > 0)
                    {
                       MessageBox.Show("WARNING..this BOL has been used before for this customer, make sure you really want to use it again.");
                    }
                    order_loose_qty.Focus();
                    return true;
                }
                else if (ActiveControl.Parent.Name.ToString() == "order_consignee_eb")
                {

                    order_address_eb.Select();
                    order_address_eb.Focus();
                    return true;
                }
                else if (ActiveControl.Parent.Name.ToString() == "order_address_eb")
                {

                    order_city_eb.Select();
                    order_city_eb.Focus();
                    return true;
                }
                else if (ActiveControl.Parent.Name.ToString() == "order_city_eb")
                {

                    order_state_eb.Select();
                    order_state_eb.Focus();
                    return true;
                }
                else if (ActiveControl.Parent.Name.ToString() == "order_state_eb")
                {

                    order_zip_eb.Select();
                    order_zip_eb.Focus();
                    return true;
                }
                else if (ActiveControl.Parent.Name.ToString() == "order_zip_eb")
                {
                  //  get_driver_facility();

                    order_BOL_eb.Select();
                    order_BOL_eb.Focus();
                    return true;
                }
                else if (ActiveControl.Parent.Name.ToString() == "order_note")
                {
                   //auto send to the grid if checkboxed

                    if (autoSend_cb.Checked)
                    {
                        send_to_orderGrid();

                    }
                    //otherwise just sit there...
                    return true;
                }
            }


            if (keyData == Keys.Enter) //On enter key for these controls fire the tab key so that it will move to the next control
            {

                if (ActiveControl.Parent.Name.ToString() == "order_loose_weight")
                {
                    SendKeys.Send("{TAB}");
                }
                else if (ActiveControl.Parent.Name.ToString() == "order_loose_qty")
                {

                    SendKeys.Send("{TAB}");

                }
                else if (ActiveControl.Parent.Name.ToString() == "order_pallets_qty")
                {

                    SendKeys.Send("{TAB}");

                }
                else if (ActiveControl.Parent.Name.ToString() == "order_pallets_weight")
                {

                    SendKeys.Send("{TAB}");

                }
                else if (ActiveControl.Parent.Name.ToString() == "order_hazmat_weight")
                {

                    SendKeys.Send("{TAB}");

                }
                else if (ActiveControl.Parent.Name.ToString() == "order_COD")
                {

                    SendKeys.Send("{TAB}");

                }

            }
            if (keyData == (Keys.Control | Keys.OemCloseBrackets))
            {
                this.order_shipper_dd.Select();
                this.order_shipper_dd.ShowDropDown();
                return true;
            }

            if (keyData == (Keys.Control | Keys.Enter)) //when ctrl-enter is pressed in the Order Entry screen
            {
                send_to_orderGrid();


                return true;
            }
        }
        return base.ProcessCmdKey(ref msg, keyData);
    }

我什至可以注释掉整个例程，它仍然可以。

Answer 1

在您发现回车键的真正问题之前考虑这样做：

private void Form1_PreviewKeyDown(object sender, PreviewKeyDownEventArgs e)
{
    if (e.KeyCode == Keys.Return)
        e.IsInputKey = true;
}

它的作用很明显，但它现在应该可以解决您的问题。有帮助吗？

Answer 2

我不确定你需要什么。您尚未定义 "process" 回车键的含义。我的最佳猜测：

1- 是否要使用回车键在文本框中换行？将 AcceptsReturn 属性从 False 更改为 True，您的文本框应该允许您使用回车键来创建新行。

2 - 使用回车键跳转到下一个控件？将 keyDown 事件添加到文本框并执行如下操作：

switch (e.KeyCode)
{
    case Keys.Enter:
        SendKeys.Send("{TAB}");
        break;
}

ProcessCmdKey 不通过回车键

ProcessCmdKey does not pass Enter Key

c#

winforms

controls

keystroke