当以其他形式调用时，DataCridview的RowCount为Always One [英] RowCount Of DataGridview is Always One when called in other form

问题描述

我有MainForm和Form2显示在Mainform的面板中。（看起来像MDI形式但不是MDI，因为我听说MDIForm是坏主意）





当我检查Mainform.cs中Form2上显示的datagridview1的RowCount或

时，datagridview1.RowCount总是一个。



我还发现 Form2.IsHandleCreated总是假的。甚至如果我看到Mainform面板中显示的Form2。



所以我通过 CreateControl 方法为Form2和datagridview1创建了句柄。



但仍然是Form2.IsHandleCreated为false。

datagridview1.ISHandle是假的ALWAYS.WHY？为什么？为什么？

也试过

我已经尝试了很多但没有找到任何解决方案。





我知道如何使用委托从不同的线程中写入值。

我已经从线程中写了Maindatagridview的值，因为我可以看到它

RowCount是我输入的内容（不止一个）。



所以我只想要解决方案为什么RowCount总是儿童Form2中的一个。

每个孩子的表格都会发生这种情况。

这个问题的问题我无法从任何其他形式向datagridview写入值

表格，甚至来自Mainform。



问题改进



//

代码1

我如何在MainForm中创建Form2

I have MainForm and Form2 is displayed in panel of Mainform.(Looks like MDI form but not MDI as I have heard that MDIForm is bad idea)


When I Check the RowCount Of datagridview1 displayed on Form2 in Mainform.cs or
any other form the datagridview1.RowCount is always one.

I have also found that Form2.IsHandleCreated is always false .Even If I see the Form2 displayed in Mainform panel.

So I have created handle by CreateControl method for Form2 and datagridview1.

but still Form2.IsHandleCreated is false.
datagridview1.ISHandle is false ALWAYS.WHY?WHY?WHY?.
also tried
I have tried a lot but not found any solution for this.


And I know how to use delegate to write values from different thread.
I have written values of Maindatagridview from thread because I can see Its
RowCount is What I have entered(more than one).

So I only want the solution for why RowCount is always one in Child Form2.
This is happening with every child form.
Becasue of this problem I am not able to write values to datagridview from any other
form ,even from Mainform.

Question Improved

//
Code 1
How I have created Form2 In MainForm

private Form CreateForm(ControlsEnum frm)
        {
            switch (frm)
            {
                case ControlsEnum.Form2:
                    return new Form2();
                 case... number of forms
                 default: return null;
            }
         }

public void ShowForm(ControlsEnum frm)
       {

           Form new_Frm = null;

          //If dictionary already contains instance of //Idictionary Interface is used
           if (controls.ContainsKey(frm))
           {

               new_Frm = controls[frm];
           }
           else
           {
               new_Frm = CreateForm(frm);
               controls[ctrl] = new_Frm;
               new_Frm.TopLevel = false;
           }

           new_Frm.Parent = this;
           new_Frm.Dock = DockStyle.Fill;
           new_Frm.BringToFront();

           ShowFormPanel_PNL.Controls.Add(new_ctrl); //this panel is in Mainform
        
            new_ctrl.Show();
      
         ////I have use stack to remove previos form //code deleted

       }

void  Mainform_Load()
{
  //  ShowForm(ControlEnum.Form2);
  if replaced the above line with below code I get results
            f2 = new Form2();
            f2.TopLevel = false;
            ShowFormPanel_PNL.Controls.Add(f2);
            f2.Show();
}

//显示Form2和Mainform时。我从Form2上的按钮动态地向gridview添加行。

//然后我点击MainFormbutton1

// When Form2 and Mainform displayed. I add dynamically rows to gridview from a button on Form2.
//then I click MainFormbutton1

private void MainFormbutton1_Click(object sender, EventArgs e)
{
           Program.f2 = f2;
           int x= Program.f2.From2GridView.Rows.Count; 
           int y = f2.From2GridView.Rows.Count; 
          // I can see the expected result.
          // but if replaced with ShowForm Rowcount is always 1.
}

推荐答案

这篇关于当以其他形式调用时，DataCridview的RowCount为Always One的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！