我正在开发一个C ++ / CLI项目，我是新手。在我的项目中，我有两个表单，一个是主页，另一个是登录页面。
我希望有一个事件，当它在登录页面成功登录时，开始从服务器获取一些jpeg图片。
我已经为它定义了委托，事件和方法，如下所示。它完全编译并运行，但是当事件被触发时，它不会运行该方法。
我找不到答案。我想知道你是否可以帮助我？
MainPage.h：
#pragma once
#include "IPPort.h"
#include "Login.h"
#include "stdafx.h"
#include "Utils.h"
namespace UIv10 {
using namespace System;
using namespace System::ComponentModel;
using namespace System::Collections;
using namespace System::Windows::Forms;
using namespace System::Data;
using namespace System::Drawing;
public ref class MainPage : public System::Windows::Forms::Form
{
public:
MainPage(void)
{
InitializeComponent();
Login ^ loginpage = gcnew Login();
loginpage->JPEGgenerate += gcnew UIv10::Login::JPEGgeneratorEventHandler(this, &MainPage::OnJPEGgenerate);
}
protected:
/// <summary>
/// Clean up any resources being used.
/// </summary>
~MainPage()
{
if (components)
{
delete components;
}
}
private: System::Windows::Forms::MenuStrip^ menuStrip1;
private: System::Windows::Forms::ToolStripMenuItem^ fileToolStripMenuItem;
private: System::Windows::Forms::ToolStripMenuItem^ connectToolStripMenuItem;
private: System::Windows::Forms::ToolStrip^ toolStrip1;
private: System::Windows::Forms::ToolStripButton^ toolStripButton1;
private: System::Windows::Forms::PictureBox^ pictureBox1;
private:
/// <summary>
/// Required designer variable.
/// </summary>
System::ComponentModel::Container ^components;
#pragma region Windows Form Designer generated code
/// <summary>
/// Required method for Designer support - do not modify
/// the contents of this method with the code editor.
/// </summary>
void InitializeComponent(void)
{
System::ComponentModel::ComponentResourceManager^ resources = (gcnew System::ComponentModel::ComponentResourceManager(MainPage::typeid));
this->menuStrip1 = (gcnew System::Windows::Forms::MenuStrip());
this->fileToolStripMenuItem = (gcnew System::Windows::Forms::ToolStripMenuItem());
this->connectToolStripMenuItem = (gcnew System::Windows::Forms::ToolStripMenuItem());
this->toolStrip1 = (gcnew System::Windows::Forms::ToolStrip());
this->toolStripButton1 = (gcnew System::Windows::Forms::ToolStripButton());
this->pictureBox1 = (gcnew System::Windows::Forms::PictureBox());
this->menuStrip1->SuspendLayout();
this->toolStrip1->SuspendLayout();
(cli::safe_cast<System::ComponentModel::ISupportInitialize^>(this->pictureBox1))->BeginInit();
this->SuspendLayout();
//
// menuStrip1
//
this->menuStrip1->Items->AddRange(gcnew cli::array< System::Windows::Forms::ToolStripItem^ >(1) { this->fileToolStripMenuItem });
resources->ApplyResources(this->menuStrip1, L"menuStrip1");
this->menuStrip1->Name = L"menuStrip1";
//
// fileToolStripMenuItem
//
this->fileToolStripMenuItem->DropDownItems->AddRange(gcnew cli::array< System::Windows::Forms::ToolStripItem^ >(1) { this->connectToolStripMenuItem });
this->fileToolStripMenuItem->Name = L"fileToolStripMenuItem";
resources->ApplyResources(this->fileToolStripMenuItem, L"fileToolStripMenuItem");
//
// connectToolStripMenuItem
//
this->connectToolStripMenuItem->Name = L"connectToolStripMenuItem";
resources->ApplyResources(this->connectToolStripMenuItem, L"connectToolStripMenuItem");
this->connectToolStripMenuItem->Click += gcnew System::EventHandler(this, &MainPage::connectToolStripMenuItem_Click);
//
// toolStrip1
//
this->toolStrip1->Items->AddRange(gcnew cli::array< System::Windows::Forms::ToolStripItem^ >(1) { this->toolStripButton1 });
resources->ApplyResources(this->toolStrip1, L"toolStrip1");
this->toolStrip1->Name = L"toolStrip1";
//
// toolStripButton1
//
resources->ApplyResources(this->toolStripButton1, L"toolStripButton1");
this->toolStripButton1->Name = L"toolStripButton1";
this->toolStripButton1->Click += gcnew System::EventHandler(this, &MainPage::toolStripButton1_Click);
//
// pictureBox1
//
resources->ApplyResources(this->pictureBox1, L"pictureBox1");
this->pictureBox1->Name = L"pictureBox1";
this->pictureBox1->TabStop = false;
//
// MainPage
//
resources->ApplyResources(this, L"$this");
this->AutoScaleMode = System::Windows::Forms::AutoScaleMode::Font;
this->Controls->Add(this->pictureBox1);
this->Controls->Add(this->toolStrip1);
this->Controls->Add(this->menuStrip1);
this->MainMenuStrip = this->menuStrip1;
this->Name = L"MainPage";
this->WindowState = System::Windows::Forms::FormWindowState::Maximized;
this->menuStrip1->ResumeLayout(false);
this->menuStrip1->PerformLayout();
this->toolStrip1->ResumeLayout(false);
this->toolStrip1->PerformLayout();
(cli::safe_cast<System::ComponentModel::ISupportInitialize^>(this->pictureBox1))->EndInit();
this->ResumeLayout(false);
this->PerformLayout();
}
#pragma endregion
private: System::Void toolStripButton1_Click(System::Object^ sender, System::EventArgs^ e) {
IPPort ^ ipportpage = gcnew IPPort();
ipportpage->Show();
}
private: System::Void connectToolStripMenuItem_Click(System::Object^ sender, System::EventArgs^ e) {
/*IPPort ^ ipportpage = gcnew IPPort();
ipportpage->Show();*/
Login^ L = gcnew Login();
L->Show();
}
void OnJPEGgenerate(System::Object^ sender,System::EventArgs^ e);
};
}
void UIv10::MainPage::OnJPEGgenerate(System::Object^ sender,System::EventArgs^ e)
{
MessageBoxA(NULL, "Failed to Login", "Attention", MB_OK);
throw gcnew System::NotImplementedException();
}
Login.h：
#include <msclr/marshal.h>
#include <Windows.h>
#ifndef Login_h
#define Login_h
bool FLogin(char use[128], char pass[64]);
#pragma once
namespace UIv10 {
using namespace System;
using namespace System::ComponentModel;
using namespace System::Collections;
using namespace System::Windows::Forms;
using namespace System::Data;
using namespace System::Drawing;
public ref class Login : public System::Windows::Forms::Form
{
public: delegate void JPEGgeneratorEventHandler(System::Object^ sender, EventArgs^ e);
public: event JPEGgeneratorEventHandler^ JPEGgenerate;
public:
Login(void)
{
InitializeComponent();
//
//TODO: Add the constructor code here
//
}
protected:
/// <summary>
/// Clean up any resources being used.
/// </summary>
~Login()
{
if (components)
{
delete components;
}
}
private: System::Windows::Forms::Button^ btnCancel2;
private: System::Windows::Forms::Button^ btnLogin;
private: System::Windows::Forms::TextBox^ txtbPassword;
private: System::Windows::Forms::TextBox^ txtbUserName;
private: System::Windows::Forms::Label^ lblPassword;
private: System::Windows::Forms::Label^ lblUserName;
private:
/// <summary>
/// Required designer variable.
/// </summary>
System::ComponentModel::Container ^components;
#pragma region Windows Form Designer generated code
/// <summary>
/// Required method for Designer support - do not modify
/// the contents of this method with the code editor.
/// </summary>
void InitializeComponent(void)
{
this->btnCancel2 = (gcnew System::Windows::Forms::Button());
this->btnLogin = (gcnew System::Windows::Forms::Button());
this->txtbPassword = (gcnew System::Windows::Forms::TextBox());
this->txtbUserName = (gcnew System::Windows::Forms::TextBox());
this->lblPassword = (gcnew System::Windows::Forms::Label());
this->lblUserName = (gcnew System::Windows::Forms::Label());
this->SuspendLayout();
//
// btnCancel2
//
this->btnCancel2->Location = System::Drawing::Point(158, 174);
this->btnCancel2->Name = L"btnCancel2";
this->btnCancel2->Size = System::Drawing::Size(71, 23);
this->btnCancel2->TabIndex = 11;
this->btnCancel2->Text = L"Cancel";
this->btnCancel2->UseVisualStyleBackColor = true;
//
// btnLogin
//
this->btnLogin->Location = System::Drawing::Point(61, 174);
this->btnLogin->Name = L"btnLogin";
this->btnLogin->Size = System::Drawing::Size(71, 23);
this->btnLogin->TabIndex = 10;
this->btnLogin->Text = L"Login";
this->btnLogin->UseVisualStyleBackColor = true;
this->btnLogin->Click += gcnew System::EventHandler(this, &Login::btnLogin_Click);
//
// txtbPassword
//
this->txtbPassword->Location = System::Drawing::Point(112, 109);
this->txtbPassword->Name = L"txtbPassword";
this->txtbPassword->PasswordChar = '*';
this->txtbPassword->Size = System::Drawing::Size(126, 20);
this->txtbPassword->TabIndex = 9;
this->txtbPassword->Text = L"roseek";
//
// txtbUserName
//
this->txtbUserName->Location = System::Drawing::Point(112, 65);
this->txtbUserName->Name = L"txtbUserName";
this->txtbUserName->Size = System::Drawing::Size(126, 20);
this->txtbUserName->TabIndex = 8;
this->txtbUserName->Text = L"roseek";
//
// lblPassword
//
this->lblPassword->Location = System::Drawing::Point(47, 117);
this->lblPassword->Name = L"lblPassword";
this->lblPassword->Size = System::Drawing::Size(59, 12);
this->lblPassword->TabIndex = 7;
this->lblPassword->Text = L"Password";
//
// lblUserName
//
this->lblUserName->AutoSize = true;
this->lblUserName->Location = System::Drawing::Point(47, 73);
this->lblUserName->Name = L"lblUserName";
this->lblUserName->Size = System::Drawing::Size(60, 13);
this->lblUserName->TabIndex = 6;
this->lblUserName->Text = L"User Name";
//
// Login
//
this->AutoScaleDimensions = System::Drawing::SizeF(6, 13);
this->AutoScaleMode = System::Windows::Forms::AutoScaleMode::Font;
this->ClientSize = System::Drawing::Size(284, 262);
this->Controls->Add(this->btnCancel2);
this->Controls->Add(this->btnLogin);
this->Controls->Add(this->txtbPassword);
this->Controls->Add(this->txtbUserName);
this->Controls->Add(this->lblPassword);
this->Controls->Add(this->lblUserName);
this->Name = L"Login";
this->Text = L"Login";
this->ResumeLayout(false);
this->PerformLayout();
}
#pragma endregion
private: System::Void btnLogin_Click(System::Object^ sender, System::EventArgs^ e) {
String ^ username;
String ^ password;
username = this->txtbUserName->Text;
password = this->txtbPassword->Text;
using namespace System::Runtime::InteropServices;
IntPtr Cusername = Marshal::StringToHGlobalAnsi(username);
char* UserName = static_cast<char*>(Cusername.ToPointer());
IntPtr Cpassword = Marshal::StringToHGlobalAnsi(password);
char* Password = static_cast<char*>(Cpassword.ToPointer());
bool Lret = FLogin(UserName, Password);
if (Lret == TRUE)
{
JPEGgenerate(this,e);
this->Close();
}
else
{
JPEGgenerate(this, e);
MessageBoxA(NULL, "Failed to Login", "Attention", MB_OK);
this->Close();
}
}
};
}
#endif
很抱歉长代码，我只是不知道问题出在哪里。
实际问题是JPEGgenerate（this，e）;运行它应该运行OnJPEGgenerate。但事实并非如此。
答案 0 :(得分：0)
这段代码对我来说似乎不对：
<input value={this.state.value} onKeyDown={this.props.changeCallback.bind( this, this.state.value)} ></input>
据我所知，你应该继续引用这样的对象，否则，它将被删除（并且不会调用适当的处理程序）
其他代码（不包含事件＆＃39; s处理程序的注册）
import pip
help(pip)