Witam.
Jestem początkującym, tworzę jakieś podstawowe aplikacje w Visual Studio C++ z użyciem forms.
Posiadam textBox, w który wpisuję ilość złotych, comboBox w którym wybieram Euro/Funty/Dolary, oraz label.
Po wyborze itemu w comboBoxie oraz wpisaniu wartości w textBox wyświetla mi się na labelu przewalutowana wartość.
- Chciałbym aby program wyświetlał MessageBox::Show("Wprowadź wartość","Uwaga",MessageBoxButtons::OK) jeżeli do textBoxu nie jest wpisana żadna wartość. Najlepiej, aby program to robił w momencie, gdy ktoś wybiera któryś z itemów w comboBoxie. Coś na zasadzie
"if (textbox jest pusty albo wartość jest równa zero)
{messagebox}
else
{wybiera się item oraz wykonują się instrukcje}
Próbowałem różnych sposobów szukając po internecie, nie działało...
- Jak zablokować [szary/wyłączony] comboBoxa, jeżeli żadna wartość nie jest wpisana do textBoxa?
#pragma once
namespace Project9 {
using namespace System;
using namespace System::ComponentModel;
using namespace System::Collections;
using namespace System::Windows::Forms;
using namespace System::Data;
using namespace System::Drawing;
/// <summary>
/// Summary for MyForm
/// </summary>
public ref class MyForm : public System::Windows::Forms::Form
{
public:
MyForm(void)
{
InitializeComponent();
//
//TODO: Add the constructor code here
//
}
protected:
/// <summary>
/// Clean up any resources being used.
/// </summary>
~MyForm()
{
if (components)
{
delete components;
}
}
private: System::Windows::Forms::Label^ label1;
private: System::Windows::Forms::ComboBox^ comboBox1;
private: System::Windows::Forms::TextBox^ textBox1;
private: System::Windows::Forms::Button^ button1;
private: System::Windows::Forms::Label^ label2;
private: System::Windows::Forms::Label^ label3;
private: System::Windows::Forms::GroupBox^ groupBox1;
private: System::Windows::Forms::RadioButton^ radioButton4;
private: System::Windows::Forms::RadioButton^ radioButton3;
private: System::Windows::Forms::RadioButton^ radioButton2;
private: System::Windows::Forms::RadioButton^ radioButton1;
private: System::ComponentModel::IContainer^ components;
protected:
private:
/// <summary>
/// Required designer variable.
/// </summary>
#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->label1 = (gcnew System::Windows::Forms::Label());
this->comboBox1 = (gcnew System::Windows::Forms::ComboBox());
this->textBox1 = (gcnew System::Windows::Forms::TextBox());
this->button1 = (gcnew System::Windows::Forms::Button());
this->label2 = (gcnew System::Windows::Forms::Label());
this->label3 = (gcnew System::Windows::Forms::Label());
this->groupBox1 = (gcnew System::Windows::Forms::GroupBox());
this->radioButton1 = (gcnew System::Windows::Forms::RadioButton());
this->radioButton2 = (gcnew System::Windows::Forms::RadioButton());
this->radioButton3 = (gcnew System::Windows::Forms::RadioButton());
this->radioButton4 = (gcnew System::Windows::Forms::RadioButton());
this->groupBox1->SuspendLayout();
this->SuspendLayout();
//
// label1
//
this->label1->Location = System::Drawing::Point(52, 74);
this->label1->Name = L"label1";
this->label1->Size = System::Drawing::Size(174, 16);
this->label1->TabIndex = 0;
this->label1->TextAlign = System::Drawing::ContentAlignment::MiddleCenter;
//
// comboBox1
//
this->comboBox1->FormattingEnabled = true;
this->comboBox1->Items->AddRange(gcnew cli::array< System::Object^ >(3) { L"Euro", L"Dolar", L"Funt" });
this->comboBox1->Location = System::Drawing::Point(135, 36);
this->comboBox1->Name = L"comboBox1";
this->comboBox1->Size = System::Drawing::Size(100, 21);
this->comboBox1->TabIndex = 1;
this->comboBox1->Text = L"Wybierz walutę";
this->comboBox1->SelectedIndexChanged += gcnew System::EventHandler(this, &MyForm::comboBox1_SelectedIndexChanged);
//
// textBox1
//
this->textBox1->Location = System::Drawing::Point(29, 36);
this->textBox1->Name = L"textBox1";
this->textBox1->Size = System::Drawing::Size(100, 20);
this->textBox1->TabIndex = 2;
this->textBox1->TextChanged += gcnew System::EventHandler(this, &MyForm::textBox1_TextChanged);
//
// button1
//
this->button1->Location = System::Drawing::Point(111, 323);
this->button1->Name = L"button1";
this->button1->Size = System::Drawing::Size(75, 23);
this->button1->TabIndex = 3;
this->button1->Text = L"Close";
this->button1->UseVisualStyleBackColor = true;
this->button1->Click += gcnew System::EventHandler(this, &MyForm::button1_Click);
//
// label2
//
this->label2->AutoSize = true;
this->label2->Location = System::Drawing::Point(26, 9);
this->label2->Name = L"label2";
this->label2->Size = System::Drawing::Size(85, 13);
this->label2->TabIndex = 5;
this->label2->Text = L"Przelicznik walut";
//
// label3
//
this->label3->AutoSize = true;
this->label3->Location = System::Drawing::Point(12, 130);
this->label3->Name = L"label3";
this->label3->Size = System::Drawing::Size(171, 13);
this->label3->TabIndex = 6;
this->label3->Text = L"Jaki jest symbol chemiczny cynku\?";
//
// groupBox1
//
this->groupBox1->Controls->Add(this->radioButton4);
this->groupBox1->Controls->Add(this->radioButton3);
this->groupBox1->Controls->Add(this->radioButton2);
this->groupBox1->Controls->Add(this->radioButton1);
this->groupBox1->Location = System::Drawing::Point(12, 162);
this->groupBox1->Name = L"groupBox1";
this->groupBox1->Size = System::Drawing::Size(105, 127);
this->groupBox1->TabIndex = 7;
this->groupBox1->TabStop = false;
//
// radioButton1
//
this->radioButton1->AutoSize = true;
this->radioButton1->Location = System::Drawing::Point(6, 19);
this->radioButton1->Name = L"radioButton1";
this->radioButton1->Size = System::Drawing::Size(38, 17);
this->radioButton1->TabIndex = 0;
this->radioButton1->TabStop = true;
this->radioButton1->Text = L"Zn";
this->radioButton1->UseVisualStyleBackColor = true;
this->radioButton1->CheckedChanged += gcnew System::EventHandler(this, &MyForm::radioButton1_CheckedChanged);
//
// radioButton2
//
this->radioButton2->AutoSize = true;
this->radioButton2->Location = System::Drawing::Point(6, 42);
this->radioButton2->Name = L"radioButton2";
this->radioButton2->Size = System::Drawing::Size(38, 17);
this->radioButton2->TabIndex = 1;
this->radioButton2->TabStop = true;
this->radioButton2->Text = L"Cu";
this->radioButton2->UseVisualStyleBackColor = true;
this->radioButton2->CheckedChanged += gcnew System::EventHandler(this, &MyForm::radioButton2_CheckedChanged);
//
// radioButton3
//
this->radioButton3->AutoSize = true;
this->radioButton3->Location = System::Drawing::Point(6, 65);
this->radioButton3->Name = L"radioButton3";
this->radioButton3->Size = System::Drawing::Size(35, 17);
this->radioButton3->TabIndex = 2;
this->radioButton3->TabStop = true;
this->radioButton3->Text = L"Cr";
this->radioButton3->UseVisualStyleBackColor = true;
this->radioButton3->CheckedChanged += gcnew System::EventHandler(this, &MyForm::radioButton3_CheckedChanged);
//
// radioButton4
//
this->radioButton4->AutoSize = true;
this->radioButton4->Location = System::Drawing::Point(6, 88);
this->radioButton4->Name = L"radioButton4";
this->radioButton4->Size = System::Drawing::Size(39, 17);
this->radioButton4->TabIndex = 3;
this->radioButton4->TabStop = true;
this->radioButton4->Text = L"Na";
this->radioButton4->UseVisualStyleBackColor = true;
this->radioButton4->CheckedChanged += gcnew System::EventHandler(this, &MyForm::radioButton4_CheckedChanged);
//
// MyForm
//
this->AutoScaleDimensions = System::Drawing::SizeF(6, 13);
this->AutoScaleMode = System::Windows::Forms::AutoScaleMode::Font;
this->ClientSize = System::Drawing::Size(312, 358);
this->Controls->Add(this->groupBox1);
this->Controls->Add(this->label3);
this->Controls->Add(this->label2);
this->Controls->Add(this->button1);
this->Controls->Add(this->textBox1);
this->Controls->Add(this->comboBox1);
this->Controls->Add(this->label1);
this->Name = L"MyForm";
this->Text = L"5,7";
this->Load += gcnew System::EventHandler(this, &MyForm::MyForm_Load);
this->groupBox1->ResumeLayout(false);
this->groupBox1->PerformLayout();
this->ResumeLayout(false);
this->PerformLayout();
}
#pragma endregion
private: System::Void comboBox1_SelectedIndexChanged(System::Object^ sender, System::EventArgs^ e) {
float a;
try
{
a = Single::Parse(textBox1->Text);
switch (comboBox1->SelectedIndex)
{
case 0:
label1->Text = (a*4.5).ToString();
break;
case 1:
label1->Text = (a*4.2).ToString();
break;
case 2:
label1->Text = (a*5.2).ToString();
break;
}
}
catch (FormatException^ e)
{
}
}
private: System::Void textBox1_TextChanged(System::Object^ sender, System::EventArgs^ e) {
float a;
try
{
a = Single::Parse(textBox1->Text);
switch (comboBox1->SelectedIndex)
{
case 0:
label1->Text = (a*4.5).ToString();
break;
case 1:
label1->Text = (a*4.2).ToString();
break;
case 2:
label1->Text = (a*5.2).ToString();
break;
}
}
catch (FormatException^ e)
{
}
}
private: System::Void button1_Click(System::Object^ sender, System::EventArgs^ e) {
if
(MessageBox::Show("Are you sure you want to close this application?", "Close", MessageBoxButtons::YesNo, MessageBoxIcon::Question) == System::Windows::Forms::DialogResult::Yes)
{
Application::Exit();
}
}
private: System::Void MyForm_Load(System::Object^ sender, System::EventArgs^ e) {
}
private: System::Void radioButton1_CheckedChanged(System::Object^ sender, System::EventArgs^ e) {
label3->Text = "1";
}
private: System::Void radioButton2_CheckedChanged(System::Object^ sender, System::EventArgs^ e) {
label3->Text = "0";
}
private: System::Void radioButton3_CheckedChanged(System::Object^ sender, System::EventArgs^ e) {
label3->Text = "0";
}
private: System::Void radioButton4_CheckedChanged(System::Object^ sender, System::EventArgs^ e) {
label3->Text = "0";
}
};
}
Z góry dziękuję za pomoc!