Can I define an array such that the first element is String, the Second is an int and the third is a textbox?
It's like when we create a List we choose type of element List<string >
Update from Comment:
Sorry I couldnt explain.I need to like this
List<string,int,object>Firstly i will set type and when i call the list i will not need to cast
thanks
create list of objects. in C# everything is derived from object
List<object> list = new List<object> {"first", 10, new TextBox()};
EDIT(To comment):
Then you should create seperate class to hold those three items , or use Tuple
List<Tuple<string,int,TextBox>> list;
You can declare an array of object and do that. You're talking about a mixed type array, right?
var arr = new object[] { "Hi", 42, 3.7, 'A' }
If you need an array that has elements without a common base-class other than object, then you're going to need an array of objects!
object[] myArray = new object[] { "Hi", 23, new TextBox() };
Note that this is not really something you should doing. If you need to associate disparate types like this, a class makes much more sense.
You want a Tuple<string,int,TextBox>, not an array.
IMHO the best way to do this is through a List<> of objects:
String s = "hey!";
int i = 156;
TextBox t = new TextBox();
List<object> list = new List<object>(3);
list.Add(s);
list.Add(i);
list.Add(t);
The reason this works is because (almost?) everything in C# derives from the base-class object
Arrays are typically homogeneous collections, which means that every object contains in the array is of the same type (or at least shares a common parent type). An array of [string, int, textbox] could be defined as an object[] but that's really misuse of arrays.
Just create a proper class which contains the 3 fields.
class MyType {
public string myString;
public int myInt;
public Listbox myListbox;
}
If you're looking make a list of string, int, textbox, you can either create a class which has those members or look at the Tuple class in .net 4.0
List<Tuple<string,int,TextBox>
Define a class that contains the 3 types then define an array that contains the new type.
Object[] myObjects = new Object(){"myString", 42, textbox1};
System.Collections.Generic.Dictionary<string, object> source = new System.Collections.Generic.Dictionary<string, object>();
source.Add("A", "Hi");
source.Add("B", 10);
source.Add("C", new TextBox());
While accessing
string str = Convert.ToString(source["A"]);
int id = Convert.ToInt16(source["B"]);
TextBox t = (TextBox)source["C"];
I will suggest that you create a Type such as
enum ItemType { Int, String, Textbox }
class MyType {
public object objValue;
public ItemType itemType;
}
List<MyType> list = new List<MyType>();
.......
You can iterate through the list or extract the list by type such as below.
var intList = list.Where(e=>e.itemType == ItemType.Int);
Of course you can achieve the above with the enum and using the reflected Type info directly from the object, but I just think it is clearer this way also more explicitly list out the type your list can hold rather than just all type in the CLR
