C # Beginner's indexer (Indexer)

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I am a beginner. NET, I hope that the predecessors to teach and exchange

An indexer (Indexer) is a new class member introduced by C # that makes an object in a class as easy and intuitive to reference as an array. Indexers are very similar to properties, but indexers contain index parameters (within []), and indexers are non-named (because this is indexed, so the "name" used in the declaration is this) and can only be applied on instance objects, not directly on the class. A class that defines an indexer allows you to access members of a class using the [] operator, just as you would access an array.

An example is given below:

Look at the code, here is the definition of the class, with an indexer definition in the middle

public class Person
{
Define two fields of information
private string name;
private string password;

Define a Name property to manipulate the name field
public string Name
{
set {name = value;}
get {return name;}
}

Define a Password property to manipulate the Password field
public string Password
{
set {password = value;}
get {return password;}
}

Defines the indexer, the Name field has an index value of 0, and the index value of the password field is 1
public string This[int Index]
{
Get
{
if (index = = 0) return name;
else if (index = = 1) return password;
else return null;
}
Set
{
if (index = = 0) name = value;
else if (index = = 1) password = value;
}
}
}

Here's how to use indexers:

protected void Page_Load (object sender, EventArgs e)
{
Declare and instantiate this class
Person p = new person ();

Using indexers to assign values to two properties of a class
P[0] = "Jarod"; As you can see, the fields in the object can be accessed as easily as an array, "Here's the assignment for name and password."
P[1] = "123456,./";

Use class properties to get two field information
Label1.Text = P.name + "/" + P.password;
}

So far, I think we should have a general grasp, then there are some details to add:

(1) Indicates whether the user can define the name of the index indicator.

A: Cannot use user-defined name is this "index table"

(2) How to avoid the problem of array crossing when using index indicator

This is a question for friends to answer.

(3) Use index indicator to bring us those convenience

A: You can not completely close a field (similar to a property), access the field value as if you were using an array, or modify

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C # Beginner's indexer (Indexer)