IList Interface
Definition
代表可依索引個別存取的非泛型物件集合。Represents a non-generic collection of objects that can be individually accessed by index.
public interface class IList : System::Collections::ICollectionpublic interface IList : System.Collections.ICollection[System.Runtime.InteropServices.ComVisible(true)]
public interface IList : System.Collections.ICollectiontype IList = interface
interface ICollection
interface IEnumerablePublic Interface IList
Implements ICollection- Derived
- Attributes
- Implements
Examples
下列範例示範如何執行 IList 介面，以建立簡單、固定大小的清單。The following example demonstrates the implementation of the IList interface to create a simple, fixed-size list.
using System;
using System.Collections;
class Program
{
static void Main()
{
var test = new SimpleList();
// Populate the List.
Console.WriteLine("Populate the List");
test.Add("one");
test.Add("two");
test.Add("three");
test.Add("four");
test.Add("five");
test.Add("six");
test.Add("seven");
test.Add("eight");
test.PrintContents();
Console.WriteLine();
// Remove elements from the list.
Console.WriteLine("Remove elements from the list");
test.Remove("six");
test.Remove("eight");
test.PrintContents();
Console.WriteLine();
// Add an element to the end of the list.
Console.WriteLine("Add an element to the end of the list");
test.Add("nine");
test.PrintContents();
Console.WriteLine();
// Insert an element into the middle of the list.
Console.WriteLine("Insert an element into the middle of the list");
test.Insert(4, "number");
test.PrintContents();
Console.WriteLine();
// Check for specific elements in the list.
Console.WriteLine("Check for specific elements in the list");
Console.WriteLine($"List contains \"three\": {test.Contains("three")}");
Console.WriteLine($"List contains \"ten\": {test.Contains("ten")}");
}
}
class SimpleList : IList
{
private object[] _contents = new object[8];
private int _count;
public SimpleList()
{
_count = 0;
}
// IList Members
public int Add(object value)
{
if (_count < _contents.Length)
{
_contents[_count] = value;
_count++;
return (_count - 1);
}
return -1;
}
public void Clear()
{
_count = 0;
}
public bool Contains(object value)
{
for (int i = 0; i < Count; i++)
{
if (_contents[i] == value)
{
return true;
}
}
return false;
}
public int IndexOf(object value)
{
for (int i = 0; i < Count; i++)
{
if (_contents[i] == value)
{
return i;
}
}
return -1;
}
public void Insert(int index, object value)
{
if ((_count + 1 <= _contents.Length) && (index < Count) && (index >= 0))
{
_count++;
for (int i = Count - 1; i > index; i--)
{
_contents[i] = _contents[i - 1];
}
_contents[index] = value;
}
}
public bool IsFixedSize
{
get
{
return true;
}
}
public bool IsReadOnly
{
get
{
return false;
}
}
public void Remove(object value)
{
RemoveAt(IndexOf(value));
}
public void RemoveAt(int index)
{
if ((index >= 0) && (index < Count))
{
for (int i = index; i < Count - 1; i++)
{
_contents[i] = _contents[i + 1];
}
_count--;
}
}
public object this[int index]
{
get
{
return _contents[index];
}
set
{
_contents[index] = value;
}
}
// ICollection members.
public void CopyTo(Array array, int index)
{
for (int i = 0; i < Count; i++)
{
array.SetValue(_contents[i], index++);
}
}
public int Count
{
get
{
return _count;
}
}
public bool IsSynchronized
{
get
{
return false;
}
}
// Return the current instance since the underlying store is not
// publicly available.
public object SyncRoot
{
get
{
return this;
}
}
// IEnumerable Members
public IEnumerator GetEnumerator()
{
// Refer to the IEnumerator documentation for an example of
// implementing an enumerator.
throw new NotImplementedException("The method or operation is not implemented.");
}
public void PrintContents()
{
Console.WriteLine($"List has a capacity of {_contents.Length} and currently has {_count} elements.");
Console.Write("List contents:");
for (int i = 0; i < Count; i++)
{
Console.Write($" {_contents[i]}");
}
Console.WriteLine();
}
}
// This code produces output similar to the following:
// Populate the List:
// List has a capacity of 8 and currently has 8 elements.
// List contents: one two three four five six seven eight
//
// Remove elements from the list:
// List has a capacity of 8 and currently has 6 elements.
// List contents: one two three four five seven
//
// Add an element to the end of the list:
// List has a capacity of 8 and currently has 7 elements.
// List contents: one two three four five seven nine
//
// Insert an element into the middle of the list:
// List has a capacity of 8 and currently has 8 elements.
// List contents: one two three four number five seven nine
//
// Check for specific elements in the list:
// List contains "three": True
// List contains "ten": False
Imports System.Collections
Public Class Program
Shared Sub Main()
Dim myList As New SimpleList()
' Populate the List.
Console.WriteLine("Populate the List")
myList.Add("one")
myList.Add("two")
myList.Add("three")
myList.Add("four")
myList.Add("five")
myList.Add("six")
myList.Add("seven")
myList.Add("eight")
myList.PrintContents()
Console.WriteLine()
' Remove elements from the list.
Console.WriteLine("Remove elements from the list")
myList.Remove("six")
myList.Remove("eight")
myList.PrintContents()
Console.WriteLine()
' Add an element to the end of the list.
Console.WriteLine("Add an element to the end of the list")
myList.Add("nine")
myList.PrintContents()
Console.WriteLine()
' Insert an element into the middle of the list.
Console.WriteLine("Insert an element into the middle of the list")
myList.Insert(4, "number")
myList.PrintContents()
Console.WriteLine()
' Check for specific elements in the list.
Console.WriteLine("Check for specific elements in the list")
Console.WriteLine($"List contains 'three': {myList.Contains("three")}")
Console.WriteLine($"List contains 'ten': {myList.Contains("ten")}")
End Sub
End Class
Public Class SimpleList
Implements IList
Private _contents(7) As Object
Private _count As Integer
Public Sub New()
_count = 0
End Sub
' IList members.
Public Function Add(ByVal value As Object) As Integer Implements IList.Add
If _count < _contents.Length Then
_contents(_count) = value
_count += 1
Return _count - 1
End If
Return -1
End Function
Public Sub Clear() Implements IList.Clear
_count = 0
End Sub
Public Function Contains(ByVal value As Object) As Boolean Implements IList.Contains
For i As Integer = 0 To Count - 1
If _contents(i) = value Then Return True
Next
Return False
End Function
Public Function IndexOf(ByVal value As Object) As Integer Implements IList.IndexOf
For i As Integer = 0 To Count - 1
If _contents(i) = value Then Return i
Next
Return -1
End Function
Public Sub Insert(ByVal index As Integer, ByVal value As Object) Implements IList.Insert
If _count + 1 <= _contents.Length AndAlso index < Count AndAlso index >= 0 Then
_count += 1
For i As Integer = Count - 1 To index Step -1
_contents(i) = _contents(i - 1)
Next
_contents(index) = value
End If
End Sub
Public ReadOnly Property IsFixedSize() As Boolean Implements IList.IsFixedSize
Get
Return True
End Get
End Property
Public ReadOnly Property IsReadOnly() As Boolean Implements IList.IsReadOnly
Get
Return False
End Get
End Property
Public Sub Remove(ByVal value As Object) Implements IList.Remove
RemoveAt(IndexOf(value))
End Sub
Public Sub RemoveAt(ByVal index As Integer) Implements IList.RemoveAt
if index >= 0 AndAlso index < Count Then
for i As Integer = index To Count - 2
_contents(i) = _contents(i + 1)
Next
_count -= 1
End If
End Sub
Public Property Item(ByVal index As Integer) As Object Implements IList.Item
Get
Return _contents(index)
End Get
Set(ByVal value As Object)
_contents(index) = value
End Set
End Property
' ICollection members.
Public Sub CopyTo(ByVal array As Array, ByVal index As Integer) Implements ICollection.CopyTo
For i As Integer = 0 To Count - 1
array.SetValue(_contents(i), index)
index += 1
Next
End Sub
Public ReadOnly Property Count() As Integer Implements ICollection.Count
Get
Return _count
End Get
End Property
Public ReadOnly Property IsSynchronized() As Boolean Implements ICollection.IsSynchronized
Get
Return False
End Get
End Property
' Return the current instance since the underlying store is not
' publicly available.
Public ReadOnly Property SyncRoot() As Object Implements ICollection.SyncRoot
Get
Return Me
End Get
End Property
' IEnumerable members.
Public Function GetEnumerator() As IEnumerator Implements IEnumerable.GetEnumerator
' Refer to the IEnumerator documentation for an example of
' implementing an enumerator.
Throw New NotImplementedException("The method or operation is not implemented.")
End Function
Public Sub PrintContents()
Console.WriteLine($"List has a capacity of {_contents.Length} and currently has {_count} elements.")
Console.Write("List contents:")
For i As Integer = 0 To Count - 1
Console.Write($" {_contents(i)}")
Next
Console.WriteLine()
End Sub
End Class
' This code produces output similar to the following:
' Populate the List:
' List has a capacity of 8 and currently has 8 elements.
' List contents: one two three four five six seven eight
'
' Remove elements from the list:
' List has a capacity of 8 and currently has 6 elements.
' List contents: one two three four five seven
'
' Add an element to the end of the list:
' List has a capacity of 8 and currently has 7 elements.
' List contents: one two three four five seven nine
'
' Insert an element into the middle of the list:
' List has a capacity of 8 and currently has 8 elements.
' List contents: one two three four number five seven nine
'
' Check for specific elements in the list:
' List contains "three": True
' List contains "ten": False
Remarks
IList 是 ICollection 介面的子代，而且是所有非泛型清單的基底介面。IList is a descendant of the ICollection interface and is the base interface of all non-generic lists. IList 的執行分為三個類別：唯讀、固定大小和可變大小。IList implementations fall into three categories: read-only, fixed-size, and variable-size. 無法修改唯讀 IList。A read-only IList cannot be modified. 固定大小的 IList 不允許加入或移除專案，但它允許修改現有的元素。A fixed-size IList does not allow the addition or removal of elements, but it allows the modification of existing elements. 可變大小的 IList 允許加入、移除和修改元素。A variable-size IList allows the addition, removal, and modification of elements.
如需此介面的泛型版本，請參閱 System.Collections.Generic.IList<T>。For the generic version of this interface, see System.Collections.Generic.IList<T>.
Properties
| Count |
取得 ICollection 中的元素數目。Gets the number of elements contained in the ICollection. (Inherited from ICollection) |
| IsFixedSize |
取得值，該值指出 IList 是否具有固定的大小。Gets a value indicating whether the IList has a fixed size. |
| IsReadOnly |
取得值，該值指出 IList 是否為唯讀。Gets a value indicating whether the IList is read-only. |
| IsSynchronized |
取得值，該值指出是否同步存取 ICollection (安全執行緒)。Gets a value indicating whether access to the ICollection is synchronized (thread safe). (Inherited from ICollection) |
| Item[Int32] |
取得或設定指定索引處的元素。Gets or sets the element at the specified index. |
| SyncRoot |
取得可用來同步存取 ICollection 的物件。Gets an object that can be used to synchronize access to the ICollection. (Inherited from ICollection) |
Methods
| Add(Object) | |
| Clear() | |
| Contains(Object) |
判斷 IList 是否包含特定值。Determines whether the IList contains a specific value. |
| CopyTo(Array, Int32) |
從特定的 ICollection 索引開始，將 Array 的項目複製到 Array。Copies the elements of the ICollection to an Array, starting at a particular Array index. (Inherited from ICollection) |
| GetEnumerator() |
傳回逐一查看集合的列舉值。Returns an enumerator that iterates through a collection. (Inherited from IEnumerable) |
| IndexOf(Object) |
決定 IList 中特定項目的索引。Determines the index of a specific item in the IList. |
| Insert(Int32, Object) |
將項目插入 IList 中指定的索引位置。Inserts an item to the IList at the specified index. |
| Remove(Object) |
從 IList 中移除特定物件第一次出現的項目。Removes the first occurrence of a specific object from the IList. |
| RemoveAt(Int32) |
移除在指定索引處的 IList 項目。Removes the IList item at the specified index. |
Extension Methods
| Cast<TResult>(IEnumerable) |
將 IEnumerable 的項目轉換成指定的型別。Casts the elements of an IEnumerable to the specified type. |
| OfType<TResult>(IEnumerable) |
根據指定的型別來篩選 IEnumerable 的項目。Filters the elements of an IEnumerable based on a specified type. |
| AsParallel(IEnumerable) |
啟用查詢的平行化作業。Enables parallelization of a query. |
| AsQueryable(IEnumerable) |
將 IEnumerable 轉換成 IQueryable。Converts an IEnumerable to an IQueryable. |