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Adding a value to a listbox item. C#

I have a list box with my desired information inside it. However I need a number to be sent when the user selects on a specific row.
ListBox data:
Test1
Test2
Test3
For example when I select Test1 in my list my I need to return the integer 2. I am asking if there is anyway I can assign the number 2 to be associated with "Test2"
listbox.Items.Add("Name displayed on list", value);

Yes, ListBox Items are of type object and you can assign any object to them, so build a class like this:
public class ListItem
{
public string Name {get; set;}
public int Value {get; set;}
public override string ToString()
{
return Name;
}
}
Now you can add ListBox Items like this:
listbox.Items.Add(new ListItem { Name = "Test1", Value = 2});
When a ListBox Item is Selected you can get its value like:
var value = ((ListItem)listbox.SelectedItem).Value;
Note that as ListBox Uses its Items .ToString() method to create Texts to show so you have to override it's ToString() method like this:
public override string ToString()
{
return Name;
}
Otherwise it will show the name of the class instead of your desired value.

As already suggested, you could specify DataSource of your listBox, then you could use conviniently SelectedValue of ListBox class. But before you have to also specify ValueMember and DisplayMember of a list box.
The most convinient in my opinion will be adding Tuple<string, int> objects to your list box and settings ValueMember to "Item2" and DisplayMember to "Item1", as Item1 willb e our string Test1 and Item2 will be integer value.
Code example:
listBox1.ValueMember = "Item2";
listBox1.DisplayMember = "Item1";
listBox1.DataSource = new Tuple<string, int>[] {
new Tuple<string, int>("Test1", 1),
new Tuple<string, int>("Test2", 2)
};
Now, in code you can just use listBox1.SelectedValue to access integer value of selected item.

WinForms Combobox: Fill with String and Object

I already have seen that there are many Topics about this,but I am not able to make them work.
I have an Combobox which shall be filled with an List of String.
this.elementBox.DataSource = this.elementList;
this.elementBox.SelectedIndexChanged += new EventHandler(this.elementBox_SelectedIndexChanged);
If I put this into the Code my GUI does not appear, I suppose the assignment of the data is wrong. I already tried Bindingsource.
Then I want to fill an Combobox with an List of Objects and this does not work either. itemData is an Dictionary with an String as key and the Objectlist as value.
box1.DataSource = itemData["ele1"];
box1.DisplayMember = "Name";
box2.DataSource = itemData["ele2"];
box2.DisplayMember = "Id";
I tried to play around with DisplayMember and Value but I am not able to get it to work.
The Type of the List is MyItem:
class myItem{ int Id; Internal data;}
class Internal {String name;}
Obviously I want to show the myItem.data.name in the Combobox, but I do not know how to get it. Furthermore what is the difference of DisplayMember and Value?

DisplayMember expects a public property not a private field
Change the classes:
class myItem
{
public int Id {get; set}
public Internal data {get;set;}
}
class Internal
{
public string Name {get; set;}
}
Note also that the property names are case sensitive. So 'name' and 'Name' are considered to be different entities.
Further, if you are adding an object of 'myItem` class, you cannot get the combo box to access the a member of a member. You will have to do the fetching yourself:
class myItem
{
public int Id {get; set}
public Internal data {get;set;}
public string Name { get { return data.Name; }}
}
Now by setting DisplayMember to "Name" it will reference the Name property of myItem which in turn accesses the data.Name property.
If the list comes to you from somewhere else (you don't own the list class and thus cannot modify it's code), you will have to wrap the objects inside another class and replace the list with a list of the wrapped objects:
class myItemWrapper
{
private myItem _myItem;
public myItemWrapper(myItem item)
{
_myItem = item;
}
public override string ToString()
{
return _myItem.data.Name;
}
public myItem Item { get { return _myItem;}}
}
then you can get rid of the DisplayMember assignment
box1.DisplayMember = "Name";
as the ToString() will be called instead.
but you have to replace the
box1.DataSource = itemData["ele1"];
with a bit more code:
var wrapper = new List<myItemWrapper>();
foreach(var item in itemData["ele1"]);
wrapper.Add(new myItemWrapper(item));
box1.DataSource = wrapper;
And don't forget that, when you are handling the selected item in the listbox that you are no longer dealing with myItem objects, but myItemWrapper objects instead. So to access the actual myItem object you will have to use the Item property of the myItemWrapper class instead.

Windows ComboBox Selected Item (populated from List<>)

I am setting a combobox item like this:
List<Object> items = new List<Object>();
items.Add(new { Text = "MyVal", Value = 1 });
cbo.DataSource = items;
It then in VS returns:
But I cannot simply now say cbo.SelectedItem.Text or cbo.SelectedItem.Value.
If i try this, I get the error
"object does not contain a definition for value and no extension method value
accepting a first argument of type object could be found"
How can I get the Value Property please
Based on great replies, I have now added this, to show that I cannot get the properties of Text or Value at all.
I've tried this code to pass the "string" into
public class ComboboxItem
{
public string Text { get; set; }
public short Value { get; set; }
public ComboboxItem(string t, short v)
{
Text = t;
Value = v;
}
}

The combo box is bound to a list containing anonymous types. You ought to use the dynamic keyword.
dynamic item = cbo.SelectedItem;
String text = item.Text;
Int32 value = item.Value;

You should add this.cbo.SelectedItem as object;
Then, for example:
public class student
{
public string name;
public int age;
}
var stu = cbo.SelectedItem as student;
string name = stu.name;
int age = stu.age;
OK,this is my first answer.

create class with Text and Value properties (ComboboxItem), then create the item list with that class. now you can do as below
ComboboxItem obj = cbo.SelectedItem as ComboboxItem;
//now you can get the obj.Value

I notice you're blanking out certain parts of your code, as of such I shall assume you're not using the object 'object' but something else, else your code wouldn't compile.
The ComboBox does not hold the datatype of its values, it all treats them as simple objects. So SelectedItem will be of type object, which should then be casted to the correct datatype in order to access the text / value property.
var myItem = cbo.SelectedItem as MyObject
if(myItem != null){
Console.WriteLine("Value is {0}", myItem.Value);
}

Searching data in datagridview

I have a datagridview that displays data from a database table. There are two columns ID and NAME.
I have a textbox in which i enter name and data of those names appear in datagridview. I have achieved searching of data but i want to search as done in comboBox. When i type "a" then all names starting with "a" should appear in datagridview. Then if i type "arn" then all names starting with "arn" should appear in datagridview. I need to know if there is a built-in method or some LOGIC that i should consider.
I am using Linq to Sql.
EDIT-1
I have made a subclass in the form class
public class Table1
{
public int ID;
public string Name;
public MyList(string _newID, string _newName)
{
_id = _newID;
_name = _newName;
}
public int _id
{
get { return ID; }
set { ID = value; }
}
public string _name
{
get { return Name; }
set { Name = value; }
}
}
Used BindingList to bind it with dataGridView1. I have applied textChanged event on a textBox1.
BindingList<Table1> tempData = new BindingList<Table1>();
string name = textBox1.Text;
var result = from row in context.Tables
where row.Name == name
select row;
foreach (Table std in result)
{
tempData.Add(new MyList(row.ID, row.Name);
}
dataGridView1.DataSource = tempData;
This is how i am doing but this searches for exact same name. I want to make it like comboBox drop down search. In which at each key typed the search result gives names/strings containing those characters.
Thanks.

Try this
Entity Framework wildcards & Linq
Like operator or using wildcards in LINQ to Entities
http://www.codeproject.com/Articles/634104/Csharp-Wildcard-Search-Using-LINQ

How to add next column to ListBox while using DataSource?

Let's say I have a ListBox called animalList. As DataSource I use following class:
class Animal
{
private int id;
private string name;
private string description;
public Animal(int id, string name, string description)
{
// implementation
}
public int Id
{
// implementation
}
public string Name
{
// implementation
}
public string Description
{
// implementation
}
}
I'd like to have 2 columns in ListBox: Name and Description. Is it possible to do so?
I managed to add one column like this:
List<Animal> animals = // LINQ sucking data from XML
animalList.MultiColumn = true;
animalList.DataSource = animals;
animalList.DisplayMember = "Name";
animalList.ValueMember = "Id";
but I cannot really figure out how to actually implement next column.

The name of the MultiColumn property can be slightly misleading. The ListBox control does not support the type of columns you're looking for.
What MultiColumn actually does is "overflow" items into a new column instead of showing a vertical scrollbar.
http://msdn.microsoft.com/en-us/library/system.windows.forms.listbox.multicolumn.aspx