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Method must have a value return type... though it has one already

I am trying to create a class that contains a header for my list-box. I have two classes that I will be inserting in the listbox. The first class runs fine, but the second one I am making so that the array is entirely of strings is telling me that a method must have a value return type. What does this mean exactly? The error at hand is "HeaderItems."
namespace RETAILITEMSBLAKE
{
class HeaderClass
{
string HeaderDescription;
string HeaderPrice;
string HeaderUnitsonHand;
public HeaderItems(string HeaderDescription, string HeaderUnitsonHand, string HeaderPrice)
{
this.HeaderDescription = HeaderDescription;
this.HeaderUnitsonHand = HeaderUnitsonHand;
this.HeaderPrice = HeaderPrice;
}
public string HeaderDescriptions
{
get
{
return HeaderDescription;
}
set
{
HeaderDescription = value;
}
}
public string HeaderUnits
{
get
{
return HeaderUnitsonHand;
}
set
{
HeaderUnitsonHand = value;
}
}
public string HeaderPrices
{
get
{
return HeaderPrice;
}
set
{
HeaderPrice = value;
}
}
}
Here is my first class that is working correctly:
namespace RETAILitemsBLAKE
{
class ItemizedClass
{
string description;
int unitsonhand;
double price;
public ItemizedClass(string description,int unitsonhand,double price)
{
this.description = description;
this.unitsonhand = unitsonhand;
this.price = price;
}
public string Description
{
get
{
return description;
}
set
{
description = value;
}
}
public double Price
{
get
{
return price;
}
set
{
price = value;
}
}
public int Quantity
{
get
{
return unitsonhand;
}
set
{
unitsonhand = value;
}
}
}
}
So, my goal is to have the HeaderClass so that I can place them as headers in my Listbox. Is there an alternate way to do such? I want to place it on top of the code here:
namespace RETAILitemsBLAKE
{
public partial class FrmItemList : Form
{
ItemizedClass[] items;
public FrmItemList()
{
InitializeComponent();
ItemizedArray();
}
private void ItemizedArray()
{
ItemizedClass jackets = new ItemizedClass("Jackets", 12, 59.95);
ItemizedClass jeans = new ItemizedClass("Jeans", 40, 34.95);
ItemizedClass shirts = new ItemizedClass("Shirts", 20, 24.95);
items = new ItemizedClass[] { jackets, jeans, shirts };
foreach (ItemizedClass RetailData in items)
{
lstRetailitems.Items.Add(RetailData.Description + "\t\t" + RetailData.Quantity + "\t" + "$" + RetailData.Price);
}
}
}
}
Would anyone be of assistance? Thank you!

You are using construct method which needs as same as class name and it didn't need to set return data type, so the method name needs to write HeaderClass in HeaderClass class otherwise it needs to set return data type to be a normal method.
class HeaderClass
{
string HeaderDescription;
string HeaderPrice;
string HeaderUnitsonHand;
public HeaderClass(string HeaderDescription, string HeaderUnitsonHand, string HeaderPrice)

How can I pass value from one subclass to another subclass in a main class C#?

I create a class named MyMainClass
namespace MyTest
{
private void frmMain_Load(object sender, EventArgs e)
{
MyMainClass myVar = new MyMainClass();
myVar.sub1.sb1A = "value 1A";
myVar.sub1.sb1B = "value 1B";
MessageBox.Show(myVar.sub2.wantPassString);
//I want to print the value "I've got value value 1A"
}
public class MyMainClass
{
public subClass1 sub1 = new subClass1();
public subClass2 sub2 = new subClass2();
public class subClass1
{
public string sb1A{get;set;}
public string sb1B{get;set;}
}
public class subClass2
{
public string sb2A{get;set;}
public string sb2B{get;set;}
// a1a is a value that I want to get from subClass1
string a1a = subClass1.sb1A;
public string wantPassString {get{return "I've got value " + a1a;}}
}
}
}
How can I pass the value from subClass1.sb1A to the string a1a or wantPassString in subClass2 ? when I call in frmMain_Load

The normal approach would be to pass the class through the constructor. This works:
public class MyMainClass
{
public MyMainClass()
{
sub1 = new subClass1();
sub2 = new subClass2(sub1);
}
public subClass1 sub1;
public subClass2 sub2;
public class subClass1
{
public string sb1A{get;set;}
public string sb1B{get;set;}
}
public class subClass2
{
public subClass2(subClass1 sub1)
{
this.sub1 = sub1;
}
public string sb2A{get;set;}
public string sb2B{get;set;}
subClass1 sub1;
public string wantPassString {get{return "I've got value " + sub1.sb1A;}}
}
}

Create a third class to hold the data.
public MainClass
{
private class sharedClass
{
internal string sb1A { get; set; }
}
public class subClass1
{
private readonly sharedClass _shared;
internal subClass1(sharedClass shared)
{
this._shared = shared;
}
public string sb1A
{
get
{
return this._shared.sb1A;
}
set
{
this._shared.sb1A = value;
}
public string sb1B{get;set;}
}
public class subClass2
{
private readonly sharedClass _shared;
public subClass2(shared s)
{
_shared = s;
}
public string sb2A{get;set;}
public string sb2B{get;set;}
public string wantPassString {get{return "I've got value " + _shared.sb1;}}
}
private readonly sharedClass _shared = new sharedClass();
private readonly subClass1 _subClass1;
private readonly subClass2 _subClass2;
public MainClass()
{
this._subClass1 = new subClass1(this._shared);
this._subClass2 = new subClass2(this._shared);
}
}

You can add additional property and method and pass it as a parameter:
public string sb2C{ get; set; }
public string getData(string strParam)
{
return sb2C= strParam;
}
Then on your frmMain_Load:
MessageBox.Show(myVar.sub2.getData(myVar.sub1.sb1B));
//This would also populate sb2C that will hold the data from the other class

C# Communication between parent form and child form

My project has two classes. The first class has information about continents and it contains also a list of objects of countries (another class).
I also declared a list of continents that contains all the continents.
I've succeeded in filling the list from a file, and succeeded to show them in a DataGridView in the same form. But the problem is that I didn't find a way to show them in a child form that contains a DataGridView.
So, how can I transfer the list of continents to the child form so that I can be able to show them in it?
I tried serialiization and deserialization, but it didn't work, I just see the name of members of continent class and nothing else.
Here are the two class and code of toolstrip that show the child form:
// first class of continent
namespace WindowsFormsApplication1
{
[Serializable]
class continent
{
//champs
private string nomc;
public string Nomc
{
get { return this.nomc; }
}
private string sup;//SUP
public string Superficie
{
get { return this.sup; }
set { this.sup = value; }
}
private string pop;//POP
public string Population
{
get { return this.pop; }
set { this.pop = value; }
}
private string dens;//DENS :
public string Densité
{
get { return this.dens; }
set { this.dens = value; }
}
private string nbp;//NBP : 54 :
public string nombre_de_Pays
{
get { return this.nbp; }
set { this.nbp = value; }
}
private string fus;//FUS )
public string Fuseaux_horaires
{
get { return this.fus; }
set { this.fus = value; }
}
private string pnb;//PNB
public string PNB_habitant
{
get { return this.pnb; }
set { this.pnb = value; }
}
//constructeur
public continent(string nom)
{
this.nomc = nom;
}
public continent()
{
// TODO: Complete member initialization
}
//list of countries of that continent
public List<country> listep = new List<country>();
}
// class of countries
namespace WindowsFormsApplication1
{
[Serializable]
class country
{
//champs
private string nom_p;
public string Nom_pays
{
get { return this.nom_p; }
set { this.nom_p = value; }
}
private string cap;//PCAP
public string Capitale
{
get { return this.cap; }
set { this.cap = value; }
}
private string sup;// PSUP
public string Superficie
{
get { return this.sup; }
set { this.sup = value; }
}
private string reg;// REG
public string Régime_politique
{
get { return this.reg; }
set { this.reg = value; }
}
private string dev;//PDEV nationale
public string Devise
{
get { return this.dev; }
set { this.dev = value; }
}
private string hym;// PHYM
public string Hymne
{
get { return this.hym; }
set { this.hym = value; }
}
private string lg;// PLG
public string Langue
{
get { return this.lg; }
set { this.lg = value; }
}
private string mo;// PMO
public string Monnaie
{
get { return this.mo; }
set { this.mo = value; }
}
private string de;
public string PDE
{
get { return this.de; }
set { this.de = value; }
}
//constructeur
public country (string nom)
{
this.nom_p = nom;
}
}
}
and the code in the form is
//liste of contnents
List<continent> listec = new List<continent>();
// i filled it from a file
//here the code of toolstrip that open the childform
private void listeContinentToolStripMenuItem_Click(object sender, EventArgs e)
{
listecont flc = new listecont();
flc.ShowDialog();
flc.MdiParent = this;
}

In your child form, add an overload to the Form constructor that takes a Form as an argument. Then when you create your child form, you can pass in an instance of your current (parent) form like, listecont flc = new listecont(this); where this is a reference of your parent form. Now your child form can make calls to parentForm.Textbox.Text = "blablabal" or what ever object you want to interact with.

Why not just add a constructor to the listecont class that takes a List<continent>? Then, the child form will have the data when it's constructed.

in your MDI child add a method:
public void SetContinentData(List<continent> list)
{
// add your DataSource to the grid
// f.e.:
dataGridView.DataSource = list;
}
and in your Toolstrip handler:
private void listeContinentToolStripMenuItem_Click(object sender, EventArgs e)
{
listecont flc = new listecont();
flc.SetContinentData(listec);
flc.ShowDialog();
flc.MdiParent = this;
}

How to set values of user control from class

I have a user control and their are many textbox on it. I add this user control to a different project and I can use it, when I write every property on UserControl. I want to set textbox fields of this user control with using a class. These are my codes:
Class:
namespace IEUserControl
{
public class IEValue
{
public string IsEmriNo { get; set; }
public string Nevi { get; set; }
public string BrutKg { get; set; }
public string NetKg { get; set; }
}
}
User Control:
namespace IsEmriUserControl
{
public partial class UC_IsEmri : UserControl
{
public UC_IsEmri()
{
InitializeComponent();
}
//private IsEmriValue _isEmri;
//public IsEmriValue isEmri
//{
// get
// {
// return _isEmri;
// }
// set
// {
// _isEmri = value;
// }
//}
public string IsEmriNo
{
get { return txtIsEmriNo.Text; }
set { txtIsEmriNo.Text = value; }
}
public string Nevi
{
get { return txtNevi.Text; }
set { txtNevi.Text = value; }
}
public string BrutKg
{
get { return txtBrutKg.Text; }
set { txtBrutKg.Text = value; }
}
public string NetKg
{
get { return txtNetKg.Text; }
set { txtNetKg.Text = value; }
}
}
}
When I use properties, I can set textbox values. However I want to set my textbox values with my Class. Can anyone give me an example setting textbox values with using class? Thank you.

Make a method/property like this
public IEValue IE_Value
{
get
{
return new IEValue() {
IsEmrino = txtIsEmriNo.Text,
Nevi = txtNevi.Text,
BrutKg = txtBrutKg.Text,
NetKg = txtNetKg.Text
};
}
set
{
txtIsEmriNo.Text = value.IsEmrino;
txtNevi.Text = value.Nevi;
txtBrutKg.Text = value.BrutKg;
txtNetKg.Text = value.NetKg;
}
}

Constructors GetInfo

I am new to C# and am working on classes and understanding them. My problem is I am not understanding how to create a Get to retrieve the private variable _yourname and Set to set the private variable _yourname.
namespace WindowsFormsApplication1
{
class InputClass
{
private string _yourName;
public string _banner;
public virtual void GetInfo();
public InputClass(String _banner)
{
_banner = "Enter your name";
}
}
}
Maybe I am using the wrong function to GetInfo. But I am also wondering when I have the GetInfo if in the () I should write _yourname in it.

In C# there are properties, which have the function of public getter and setter methods in other languages:
class InputClass
{
private string _yourName;
public string _banner;
public InputClass(String _banner)
{
this._banner = _banner;
}
public string YourName
{
get { return _yourName; }
set { _yourName = value; }
}
}
But you can use auto properties, if you want:
class InputClass
{
public InputClass(String _banner)
{
Banner = _banner;
}
public string YourName
{
get; set;
}
public string Banner
{
get; set;
}
}

It sounds like you are trying to provide access to the _yourName field. If so then just use a property
class InputClass {
public string YourName {
get { return _yourName; }
set { _yourName = value; }
}
...
}
Now consumers of InputClass can access it as if it were a read only field.
InputClass ic = ...;
string yourName = ic.YourName;
ic.YourName = "hello";
Note: C# provides a special syntax for simple properties like this which are just meant to be wrappers over private fields. It's named auto-implemented properties
class InputClass {
public string YourName { get; set; }
}

You can override getters and settings using the get and set keywords. For example:
class InputClass
{
private string _yourName;
private string _banner;
public YourName
{
get { return _yourName; }
set { _yourName = value; }
}
public Banner
{
get { return _banner; }
set { _banner = value; }
}
public InputClass(String banner)
{
_banner = banner;
}
}

1.) Use properties instead of members, you get a free accessor (get) and mutator (set).
public string YourName { get; set; }
public string Banner { get; set; }
2.) You can take advantage of the default constructor, and declare it on the fly.
//the old way:
InputClass myClass = new InputClass();
myClass.YourName = "Bob";
myClass.Banner = "Test Banner";
//on the fly:
InputClass myClass = new InputClass()
{
YourName = "Bob",
Banner = "Test Banner"
}