Visual C++重新加載表單以查看隱藏後的數據

我有一個具有多種表單的程序，我需要允許用戶在表單之間來回切換。問題是，當我點擊「下一步」後隱藏form1並繼續form2，然後按「返回」回到form1，我輸入的所有數據都消失了。Visual C++重新加載表單以查看隱藏後的數據

我曾想過將所有內容寫入文本文件，然後再讀取所有數據。但這是額外的代碼，我認爲這是不必要的。

代碼： Form1中：

public: System::Void to_page_2_Click(System::Object^ sender, System::EventArgs^ e) { 
Page2^p2 = gcnew Page2(this); 
    p2->Show(); 
    this->Hide(); 
}

窗體2：

private: System::Void back_Pg1_Click(System::Object^ sender, System::EventArgs^ e) { 
    this->Hide(); 
PreviousForm->Show();

有參與，使代碼工作，來回走額外的代碼。但這不是問題。我只想知道刷新Form1而不是加載新的Form1的代碼。

感謝您的幫助。我希望我很清楚。我使用Visual Studio 2015年社區

來源

2016-01-14 Jordan

兩個可能的解決方案是：

1）直接回答這個問題，一個可能的解決方案是使用的ShowDialog（）（未在事件處理程序），而不是顯示（）
這樣做：

namespace formSwitchTest 
{ 
    ref class tcFormBase : System::Windows::Forms::Form 
    { 
    public: 

     tcFormBase(
      System::String^aTitle, 
      System::Windows::Threading::Dispatcher^aMainDispatcher) : 
      mpcForm(nullptr), 
      mMainDispatcher(aMainDispatcher) 
     { 

      this->SuspendLayout(); 
      this->AutoSize = true; 

      mpcSwitchButton = gcnew System::Windows::Forms::Button(); 
      mpcSwitchButton->AutoSize = true; 
      mpcSwitchButton->Click += gcnew System::EventHandler(this, &formSwitchTest::tcFormBase::ButtonClicked); 
      mpcSwitchButton->Text = "Click to leave "; 
      mpcSwitchButton->Text += aTitle; 
      mpcSwitchButton->Dock = System::Windows::Forms::DockStyle::Top; 

      mpcExitButton = gcnew System::Windows::Forms::Button(); 
      mpcExitButton->AutoSize = true; 
      mpcExitButton->Click += gcnew System::EventHandler(this, &formSwitchTest::tcFormBase::Exit); 
      mpcExitButton->Text = "click to exit"; 
      mpcExitButton->Dock = System::Windows::Forms::DockStyle::Bottom; 

      mpcTextBox = gcnew System::Windows::Forms::TextBox(); 
      mpcTextBox->Width = 200; 
      mpcTextBox->AutoSize = true; 
      mpcTextBox->Text = "enter text here"; 
      mpcTextBox->Dock = System::Windows::Forms::DockStyle::Left; 

      this->Controls->Add(mpcTextBox); 
      this->Controls->Add(mpcSwitchButton); 
      this->Controls->Add(mpcExitButton); 
      this->ResumeLayout(); 
      this->PerformLayout(); 
     } 

     void SetOtherForm(System::Windows::Forms::Form^apcForm) 
     { 
      mpcForm = apcForm; 

      // save this action to perform multiple times later 
      mShowOtherForm = gcnew System::Action(this, &formSwitchTest::tcFormBase::ShowOtherForm); 
     } 

     void ShowDialog() 
     { 
      System::Windows::Forms::Form::ShowDialog(); 
     } 

    private: 

     void ShowOtherForm() 
     { 
      // perform the blocking ShowDialog() because it works better than Show() 
      mpcForm->ShowDialog(); 
     } 

     void Exit(System::Object^apcSender, System::EventArgs^apcArgs) 
     { 
      // stop the blocking ShowDialog() 
      this->Hide(); 

      // tell the dispatcher to stop, which will stop the Run() call 
      mMainDispatcher->BeginInvokeShutdown(System::Windows::Threading::DispatcherPriority::Normal); 
     } 

     void ButtonClicked(System::Object^apcSender, System::EventArgs^apcArgs) 
     { 
      // stop the blocking ShowDialog() 
      this->Hide(); 

      // BeginInvoke() to prevent blocking 
      mMainDispatcher->BeginInvoke(mShowOtherForm); 
     } 

     System::Windows::Forms::Form^mpcForm; 
     System::Windows::Forms::Button^mpcSwitchButton; 
     System::Windows::Forms::Button^mpcExitButton; 
     System::Windows::Forms::TextBox^mpcTextBox; 
     System::Windows::Threading::Dispatcher^mMainDispatcher; 
     System::Action^mShowOtherForm; 
    }; 
} 

int main(void) 
{ 
    System::Windows::Threading::Dispatcher^lpcMainDispatcher = 
     System::Windows::Threading::Dispatcher::CurrentDispatcher; 

    // the only reason for each form being of the same base is for ease of the test 
    formSwitchTest::tcFormBase^lpcMainForm = gcnew formSwitchTest::tcFormBase(
     "main", lpcMainDispatcher); 
    formSwitchTest::tcFormBase^lpcSecondForm = gcnew formSwitchTest::tcFormBase(
     "second", lpcMainDispatcher); 

    // exchange pointers to each other 
    lpcMainForm->SetOtherForm(lpcSecondForm); 
    lpcSecondForm->SetOtherForm(lpcMainForm); 

    // begin invoke to put the start action in the queue 
    lpcMainDispatcher->BeginInvoke(gcnew System::Action(lpcMainForm, &formSwitchTest::tcFormBase::ShowDialog)); 

    // process the dispatcher queue and wait for it to be shut down 
    System::Windows::Threading::Dispatcher::Run(); 
}

2）它可能會更好，更接近你在找什麼使用控件類，而不是形式

namespace formSwitchTest 
{ 
    ref class tcCtrlBase : System::Windows::Forms::UserControl 
    { 
    public: 
     tcCtrlBase(
      System::String^aTitle, 
      System::Windows::Forms::Form^apcContainerForm) : 
      mpcCtrl(nullptr), 
      mpcContainerForm(apcContainerForm) 
     { 

      this->SuspendLayout(); 
      this->AutoSize = true; 

      mpcSwitchButton = gcnew System::Windows::Forms::Button(); 
      mpcSwitchButton->AutoSize = true; 
      mpcSwitchButton->Click += gcnew System::EventHandler(this, &formSwitchTest::tcCtrlBase::ButtonClicked); 
      mpcSwitchButton->Text = "Click to leave "; 
      mpcSwitchButton->Text += aTitle; 
      mpcSwitchButton->Dock = System::Windows::Forms::DockStyle::Top; 

      mpcExitButton = gcnew System::Windows::Forms::Button(); 
      mpcExitButton->AutoSize = true; 
      mpcExitButton->Click += gcnew System::EventHandler(this, &formSwitchTest::tcCtrlBase::Exit); 
      mpcExitButton->Text = "click to exit"; 
      mpcExitButton->Dock = System::Windows::Forms::DockStyle::Bottom; 

      mpcTextBox = gcnew System::Windows::Forms::TextBox(); 
      mpcTextBox->Width = 200; 
      mpcTextBox->AutoSize = true; 
      mpcTextBox->Text = "enter text here"; 
      mpcTextBox->Dock = System::Windows::Forms::DockStyle::Left; 

      this->Controls->Add(mpcTextBox); 
      this->Controls->Add(mpcSwitchButton); 
      this->Controls->Add(mpcExitButton); 
      this->ResumeLayout(); 
      this->PerformLayout(); 
     } 

     void SetOtherCtrl(System::Windows::Forms::UserControl^apcCtrl) 
     { 
      mpcCtrl = apcCtrl; 
     } 

    private: 

     void ShowOtherForm() 
     { 
      mpcCtrl->Show(); 
     } 

     void Exit(System::Object^apcSender, System::EventArgs^apcArgs) 
     { 
      mpcContainerForm->Hide(); 
     } 

     void ButtonClicked(System::Object^apcSender, System::EventArgs^apcArgs) 
     { 
      this->Hide(); 
      mpcCtrl->Show(); 
     } 

     System::Windows::Forms::UserControl^mpcCtrl; 
     System::Windows::Forms::Button^mpcSwitchButton; 
     System::Windows::Forms::Button^mpcExitButton; 
     System::Windows::Forms::TextBox^mpcTextBox; 
     System::Windows::Forms::Form^mpcContainerForm; 
    }; 
} 

int main(void) 
{ 
    System::Windows::Forms::Form^lpcContainerForm = gcnew System::Windows::Forms::Form(); 

    formSwitchTest::tcCtrlBase^lpcMainForm = gcnew formSwitchTest::tcCtrlBase(
     "main", lpcContainerForm); 
    formSwitchTest::tcCtrlBase^lpcSecondForm = gcnew formSwitchTest::tcCtrlBase(
     "second", lpcContainerForm); 

    lpcMainForm->SetOtherCtrl(lpcSecondForm); 
    lpcSecondForm->SetOtherCtrl(lpcMainForm); 

    lpcContainerForm->AutoSize = true; 
    lpcContainerForm->Controls->Add(lpcMainForm); 
    lpcContainerForm->Controls->Add(lpcSecondForm); 
    lpcContainerForm->ShowDialog(); 
}

來源

2016-01-19 22:14:13 Chad

Visual C++重新加載表單以查看隱藏後的數據

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