Set an 'int' in one event and use it in another event - c#

I'm making a little something in Windows Form (C# Visual Studio)
But I need to know how I can set an int and then to use it in another event. For example, :
private void BtnYes_Click(object sender, EventArgs e)
{
int yes = 1;
int no = 0;
timer1.Start();
}
private void timer1_Tick(object sender, EventArgs e)
{
if (yes == 1) {
//EVENT
}
}
When I do this I get some errors. Can anyone help me with this? Or just tell me how to do something like this using a different technique?

U need to use a field for this:
private int _yes;
private void BtnYes_Click(object sender, EventArgs e)
{
_yes = 1;
int no = 0;
timer1.Start();
}
private void timer1_Tick(object sender, EventArgs e)
{
if (_yes == 1) {
//EVENT
}
}

The variable "yes" you are declaring is only visible in the scope of the method. By making it a field of class, this would make it visible to all methods in the class (when private).
class YourClass
{
private int yes = 1;
private int no = 0;
private void BtnYes_Click(object sender, EventArgs e)
{
//Remove the type declaration here to use the class field instead. If you leave the type declaration, the variable here will be used instead of the class field.
yes = 1;
no = 0;
timer1.Start();
}
private void timer1_Tick(object sender, EventArgs e)
{
if (yes == 1) {
//EVENT
}
}
}

Related

Call method inside a Form

Hi I am learning C# and struggling with a Form in which a btnCalc_click event should call a method calcArea and produce the output in a textBox1.text
the error is in row: textBox1.Text = calcArea.ToString();
who can help with with the correct syntax ?
namespace Meetkunde
{
public partial class Form1 : Form
{
public Form1()
{
InitializeComponent();
}
private void Form1_Load(object sender, EventArgs e)
{
}
private void txbLengte_TextChanged(object sender, EventArgs e)
{
double length = 0;
length = double.Parse(txbLength.Text);
}
private void txbBreedte_TextChanged(object sender, EventArgs e)
{
double width = 0;
width = double.Parse(txbWidth.Text);
}
public double calcArea(double length, double width)
{
double area = 0;
area = (length * width);
return area;
}
private void label3_Click(object sender, EventArgs e)
{
}
private void textBox1_TextChanged(object sender, EventArgs e)
{
}
private void btnCalc_Click(object sender, EventArgs e)
{
textBox1.Text = calcArea.ToString();
}
}
}
As I mentioned above - you need to pass the method the parameters as you defined them in the method. You don't need Text Changed events for this either - plus they aren't doing anything.
Try changing your code to something like (not real sure of what exactly you named textboxes):
private void btnCalc_Click(object sender, EventArgs e)
{
double width = Convert.ToDouble(txbBreedte.Text);//txbWidth.Text?
double length= Convert.ToDouble(txbLengte.Text);//txbLength.Text?
textBox1.Text = calcArea(length, width).ToString();
}
calcArea.ToString();
when you are calling this, you aren't calling the function, you are referencing the function, not the return
do
calcArea(parameters).ToString();
replace parameters with what you want to calculate.

Call a LIST<DOUBLE> inside button1 click event into button2 click event in c#

I have two buttons in my C# windows form application. Button1 and Button2.
i want to use a variable and a list calculated in Button1's event as an input variable in Button2's event. how can I do that? Example:
private void button1_Click(object sender, EventArgs e)
{
int a;
// some steps
// after these steps, assume a gets the value of 5 so a = 5 at this point.
// also there is a list which gets its values after these steps
List<double> parameterValues = new List<double> {
i.GetDouble(), S.GetDouble(), L.GetDouble(),B.GetDouble()
};
}
Here is the code for button2 event, in this I want to be able to use the value of a calculated in button1's code.
private void button2_Click(object sender, EventArgs e)
{
int b = a + 5;
// some code to call the list as well
}
You have to make int a global in order to use it in both buttons.
public int a;
private void button1_Click(object sender, EventArgs e)
{
a = 5;
// some steps
// after these steps, assume a gets the value of 5 so a = 5 at this point.
}
private void button2_Click(object sender, EventArgs e)
{
int b = a + 5;
}
You have a scope issue currently. The value you want to use inside button click 2 must be at least modular to the forms class in order to use in both methods. In this example, "outerValue" is modular and can be accessed by both. Have a read through this article to get a better overview of variable scope.
https://msdn.microsoft.com/en-us/library/ms973875.aspx
public partial class Form1 : Form
{
private int outerValue = 0;
public Form1()
{
InitializeComponent();
}
private void Form1_Load(object sender, EventArgs e)
{
}
private void button1_Click(object sender, EventArgs e)
{
int a = 5;
outerValue = a + 5;
}
private void button2_Click(object sender, EventArgs e)
{
int b = outerValue + 5;
}
}

How do I define custom eventargs for an event?

I would like to create custom Eventargs for a series of events. I am using a third party X/Y scope where I plot Strength vs frequency. This scope has the ability to place "Markers" on it which are just little triangles at various frequencies. These markers support events such as when the mouse enters the marker, a click is performed, and the mouse leaves the marker. So for two markers, here is the code:
private void createEvents()
{
this.scope2.MarkerGroups[0].Click += new EventHandler(Marker0_Click);
this.scope2.MarkerGroups[0].MouseEnter += new EventHandler(Marker0_Enter);
this.scope2.MarkerGroups[0].MouseLeave += new EventHandler(Marker0_Leave);
this.scope2.MarkerGroups[1].Click += new EventHandler(Marker1_Click);
this.scope2.MarkerGroups[1].MouseEnter += new EventHandler(Marker1_Enter);
this.scope2.MarkerGroups[1].MouseLeave += new EventHandler(Marker1_Leave);
}
// And now the event handlers
private void Marker0_Click(object sender, EventArgs e)
{
//do something;
}
private void Marker0_Enter(object sender, EventArgs e)
{
//do something
}
private void Marker0_Leave(object sender, EventArgs e)
{
// do something
}
private void Marker1_Click(object sender, EventArgs e)
{
//do something;
}
private void Marker1_Enter(object sender, EventArgs e)
{
//do something
}
private void Marker1_Leave(object sender, EventArgs e)
{
// do something
}
Now this is fine for two markers....but I need 80 of them. I could just write the whole thing out but there has to be a better way. So I started like this:
private void createMarkerEvents()
{
for (int i = 0; i < 80; i++)
{
this.scope2.MarkerGroups[i].Click += new EventHandler(Marker_Click);
this.scope2.MarkerGroups[i].MouseEnter += new EventHandler(Marker_Enter);
this.scope2.MarkerGroups[i].MouseLeave += new EventHandler(Marker_Leave);
}
}
private void Marker_Click(object sender, EventArgs e)
{
//do something;
}
private void Marker_Enter(object sender, EventArgs e)
{
//do something
}
private void Marker_Leave(object sender, EventArgs e)
{
// do something
}
So the question is how can I pass the actual marker number from the events to the event handlers?
There has got to be a way.
Thanks, Tom
If you want to identify marker group you may cast object sender to a MarkerGroup object
private void AnyMarker_Click(object sender, EventArgs e)
{
MarkerGroup group = (MarkerGroup)sender;
int indexOfMarkerGroup = this.scope2.MarkerGroups.IndexOf(group);
//do something;
}
OFF: You should define a custom EventArgs class:
public class MyEventArgs : EventArgs
{
public int MyCustomProperty {get;set;}
}
Then use it in your event:
public event EventHandler<MyEventArgs> ButtonPressed;
Fire event using custom args:
if(ButtonPressed != null)
{
ButtonPressed(this, new MyEventArgs { MyCustomProperty = 1 });
}
EDIT
Full example:
private void createMarkerEvents()
{
for (int i = 0; i < 80; i++)
{
this.scope2.MarkerGroups[i].Click += new EventHandler(Marker_Click);
this.scope2.MarkerGroups[i].MouseEnter += new EventHandler(Marker_Enter);
this.scope2.MarkerGroups[i].MouseLeave += new EventHandler(Marker_Leave);
}
}
private void Marker_Click(object sender, EventArgs e)
{
// When markergroup fires and event, it passes reference to itself as `sender` parameter
// so we can get access it
MarkerGroup mg = (MarkerGroup)sender; // this marker has fired a click event
// Now you know which marker has fired event
// if you want to determine it's index in MarkerGroups collection:
int index = this.scope2.MarkerGroup.IndexOf(mg);
// now you know MarkerGroup and it's index
}
private void Marker_Enter(object sender, EventArgs e)
{
//do something
}
private void Marker_Leave(object sender, EventArgs e)
{
// do something
}

Variable Scoping in c#.net

Hi it might sound a simple task but i am a bit confused here
I have an event :
private void ManReg_Click(object sender, EventArgs e)
{
int store = data[0];
}
and then another event function like :
private void measurementsRead_Click(object sender, EventArgs e)
{
}
I would like to use the variable "store" in the second function. How can I ?
The form is declared as follows :
namespace myRfid
{
public partial class Form1 : Form
{
}
}
You should put variable onto the class level
class ...
{
private int store;
private void ManReg_Click(object sender, EventArgs e)
{
store = data[0];
}
private void measurementsRead_Click(object sender, EventArgs e)
{
// use store
}
}
You can set it as shown in below code in your class but private as it would be used within class only as shown below :-
private int store;
private void ManReg_Click(object sender, EventArgs e)
{
this.store = data[0];
}
private void measurementsRead_Click(object sender, EventArgs e)
{
this.store//// however you want to use
}

Stumped on calculator operations in C#

I was making a calculator using Windows Forms Application and I'm currently stumped.
Here's my application so far, it can only do addition, but any amount of numbers.
using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Windows.Forms;
namespace Calculator
{
public partial class Form1 : Form
{
int num;
int answer = 0;
int i;
public Form1()
{
InitializeComponent();
}
private void plusButton_Click(object sender, EventArgs e)
{
answer += System.Convert.ToInt32(textBox1.Text);
ClearTextbox();
}
private void minusButton_Click(object sender, EventArgs e)
{
//answer -= System.Convert.ToInt32(textBox1.Text);
//ClearTextbox();
}
private void Form1_Load(object sender, EventArgs e)
{
}
private void divideButton_Click(object sender, EventArgs e)
{
}
private void multiplyButton_Click(object sender, EventArgs e)
{
}
private void textBox1_TextChanged(object sender, EventArgs e)
{
}
private void button1_Click(object sender, EventArgs e)
{
num = 1;
displayInt(num);
}
private void button2_Click(object sender, EventArgs e)
{
num = 2;
displayInt(num);
}
private void button3_Click(object sender, EventArgs e)
{
num = 3;
displayInt(num);
}
private void button4_Click(object sender, EventArgs e)
{
num = 4;
displayInt(num);
}
private void button5_Click(object sender, EventArgs e)
{
num = 5;
displayInt(num);
}
private void button6_Click(object sender, EventArgs e)
{
num = 6;
displayInt(num);
}
private void button7_Click(object sender, EventArgs e)
{
num = 7;
displayInt(num);
}
private void button8_Click(object sender, EventArgs e)
{
num = 8;
displayInt(num);
}
private void button9_Click(object sender, EventArgs e)
{
num = 9;
displayInt(num);
}
private void button0_Click(object sender, EventArgs e)
{
num = 0;
displayInt(num);
}
private void resetButton_Click(object sender, EventArgs e)
{
ClearTextbox();
num = 0;
answer = 0;
}
public void displayInt(int num)
{
textBox1.Text = textBox1.Text + num.ToString();
}
public void ClearTextbox()
{
textBox1.Clear();
}
public void DisplayAnswer(int answer)
{
answer += System.Convert.ToInt32(textBox1.Text); //Answer = Answer + Textbox Stuff
textBox1.Clear();
textBox1.Text = answer.ToString();
}
private void equalsButton_Click(object sender, EventArgs e)
{
DisplayAnswer(answer);
num = 0;
answer = 0;
}
}
}
I'm not sure if there's a way to wait until another number key is pressed, and then do x + y. I heard about event handlers, but it's quite a vague topic to me.
Here's a picture: http://img196.imageshack.us/img196/4127/12464e13e5154a949a9a457.png
*I want it to be able to do operations to more then 2 numbers.
Thanks!
Your code is a bit messy and it's hard to figure out your intent. Help with this code will be long in coming. I suggest following this simple calculator tutorial. It explains the concepts and steps very nicely, including button events.
You would need to have a "+"-button and a "="-button. Then your calculator has two number fields and two states:
1) Entering first number
2) Entering second number
You could have a variable saying which number is being entered.
int field = 1;
When pressing a digit button, this digit has to be appended to the corresponding field.
When pressing the "+"-button change the state to
field = 2;
Now the digits will be appended to the second field.
When you press the "="-button, convert the two numbers, which are still strings now, to int's, add them and output them to a result field. Set the state back to
field = 1;
Also a "clear"-button would clear the fields and set field = 1;
Note: As Paul Sasik says, your code is a bit messy. I would help, if you gave your buttons meaningful names like btnDigit1, btnDigit2, btnPlus, btnEquals, btnClear. When you double-click a button in the designer an event handler like btnPlus_Click will be created. This is clearer than button17_Click.

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