IList 介面
定義
重要
部分資訊涉及發行前產品,在發行之前可能會有大幅修改。 Microsoft 對此處提供的資訊,不做任何明確或隱含的瑕疵擔保。
表示可依索引個別存取之物件的非泛型集合。
public interface class IList : System::Collections::ICollection
public interface IList : System.Collections.ICollection
[System.Runtime.InteropServices.ComVisible(true)]
public interface IList : System.Collections.ICollection
type IList = interface
interface ICollection
interface IEnumerable
[<System.Runtime.InteropServices.ComVisible(true)>]
type IList = interface
interface ICollection
interface IEnumerable
Public Interface IList
Implements ICollection
- 衍生
- 屬性
- 實作
範例
下列範例示範如何實作 IList 介面,以建立簡單的固定大小清單。
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
備註
IList 是 ICollection 介面的子代,而且是所有非泛型清單的基底介面。 IList 實作分為三個類別:只讀、固定大小和可變大小。 無法修改唯讀 IList。 固定大小的 IList 不允許新增或移除專案,但它允許修改現有的專案。 可變大小 IList 允許新增、移除和修改元素。
如需此介面的泛型版本,請參閱 System.Collections.Generic.IList<T>。
屬性
Count |
取得包含在 ICollection中的項目數目。 (繼承來源 ICollection) |
IsFixedSize |
取得值,指出 IList 是否有固定大小。 |
IsReadOnly |
取得值,指出 IList 是否為唯讀。 |
IsSynchronized |
取得值,指出是否同步存取 ICollection (線程安全)。 (繼承來源 ICollection) |
Item[Int32] |
取得或設定位於指定索引處的專案。 |
SyncRoot |
取得對象,這個物件可用來同步存取 ICollection。 (繼承來源 ICollection) |
方法
Add(Object) |
將專案加入至 IList。 |
Clear() |
從 IList移除所有專案。 |
Contains(Object) |
判斷 IList 是否包含特定值。 |
CopyTo(Array, Int32) |
從特定 Array 索引開始,將 ICollection 的專案複製到 Array。 (繼承來源 ICollection) |
GetEnumerator() |
傳回逐一查看集合的列舉值。 (繼承來源 IEnumerable) |
IndexOf(Object) |
決定 IList中特定專案的索引。 |
Insert(Int32, Object) |
將專案插入指定索引處的 IList。 |
Remove(Object) |
從 IList移除第一個出現的特定物件。 |
RemoveAt(Int32) |
拿掉位於指定索引處的 IList 專案。 |
擴充方法
Cast<TResult>(IEnumerable) |
將 IEnumerable 的項目轉換成指定的型別。 |
OfType<TResult>(IEnumerable) |
根據指定的型別篩選 IEnumerable 的專案。 |
AsParallel(IEnumerable) |
啟用查詢的平行處理。 |
AsQueryable(IEnumerable) |
將 IEnumerable 轉換成 IQueryable。 |