ArrayList.Insert 方法
将元素插入 ArrayList 的指定索引处。
**命名空间:**System.Collections
**程序集:**mscorlib(在 mscorlib.dll 中)
语法
声明
Public Overridable Sub Insert ( _
index As Integer, _
value As Object _
)
用法
Dim instance As ArrayList
Dim index As Integer
Dim value As Object
instance.Insert(index, value)
public virtual void Insert (
int index,
Object value
)
public:
virtual void Insert (
int index,
Object^ value
)
public void Insert (
int index,
Object value
)
public function Insert (
index : int,
value : Object
)
参数
- index
从零开始的索引,应在该位置插入 value。
- value
要插入的 Object。该值可以为 空引用(在 Visual Basic 中为 Nothing)。
异常
异常类型 | 条件 |
---|---|
index 小于零。 - 或 - index 大于 Count。 |
|
ArrayList 为只读。 - 或 - ArrayList 具有固定大小。 |
备注
ArrayList 接受 空引用(在 Visual Basic 中为 Nothing) 作为有效值并且允许重复的元素。
如果 Count 已经等于 Capacity,则在添加新元素之前,会通过自动重新分配内部数组并将现有元素将复制到新数组中,来使 ArrayList 的容量增加。
如果 index 等于 Count,则将 value 添加到 ArrayList 的结尾处。
在连续元素集合(如列表)中,插入点后的元素会下移以容纳新的元素。如果该集合已编制索引,则还更新已移动的元素的索引。此行为不适用于元素按概念分组到存储桶中的集合(如哈希表)。
此方法的运算复杂度为 O(n),其中 n 是 Count。
示例
下面的代码示例演示如何向 ArrayList 中插入元素。
Imports System
Imports System.Collections
Imports Microsoft.VisualBasic
Public Class SamplesArrayList
Public Shared Sub Main()
' Creates and initializes a new ArrayList using Insert instead of Add.
Dim myAL As New ArrayList()
myAL.Insert(0, "The")
myAL.Insert(1, "fox")
myAL.Insert(2, "jumps")
myAL.Insert(3, "over")
myAL.Insert(4, "the")
myAL.Insert(5, "dog")
' Creates and initializes a new Queue.
Dim myQueue As New Queue()
myQueue.Enqueue("quick")
myQueue.Enqueue("brown")
' Displays the ArrayList and the Queue.
Console.WriteLine("The ArrayList initially contains the following:")
PrintValues(myAL)
Console.WriteLine("The Queue initially contains the following:")
PrintValues(myQueue)
' Copies the Queue elements to the ArrayList at index 1.
myAL.InsertRange(1, myQueue)
' Displays the ArrayList.
Console.WriteLine("After adding the Queue, the ArrayList now contains:")
PrintValues(myAL)
' Search for "dog" and add "lazy" before it.
myAL.Insert(myAL.IndexOf("dog"), "lazy")
' Displays the ArrayList.
Console.WriteLine("After adding ""lazy"", the ArrayList now contains:")
PrintValues(myAL)
' Add "!!!" at the end.
myAL.Insert(myAL.Count, "!!!")
' Displays the ArrayList.
Console.WriteLine("After adding ""!!!"", the ArrayList now contains:")
PrintValues(myAL)
' Inserting an element beyond Count throws an exception.
Try
myAL.Insert(myAL.Count + 1, "anystring")
Catch myException As Exception
Console.WriteLine("Exception: " + myException.ToString())
End Try
End Sub
Public Shared Sub PrintValues(myList As IEnumerable)
Dim obj As [Object]
For Each obj In myList
Console.Write(" {0}", obj)
Next obj
Console.WriteLine()
End Sub 'PrintValues
End Class
' This code produces the following output.
'
' The ArrayList initially contains the following:
' The fox jumps over the dog
' The Queue initially contains the following:
' quick brown
' After adding the Queue, the ArrayList now contains:
' The quick brown fox jumps over the dog
' After adding "lazy", the ArrayList now contains:
' The quick brown fox jumps over the lazy dog
' After adding "!!!", the ArrayList now contains:
' The quick brown fox jumps over the lazy dog !!!
' Exception: System.ArgumentOutOfRangeException: Insertion index was out of range. Must be non-negative and less than or equal to size.
' Parameter name: index
' at System.Collections.ArrayList.Insert(Int32 index, Object value)
' at SamplesArrayList.Main()
using System;
using System.Collections;
public class SamplesArrayList {
public static void Main() {
// Creates and initializes a new ArrayList using Insert instead of Add.
ArrayList myAL = new ArrayList();
myAL.Insert( 0, "The" );
myAL.Insert( 1, "fox" );
myAL.Insert( 2, "jumps" );
myAL.Insert( 3, "over" );
myAL.Insert( 4, "the" );
myAL.Insert( 5, "dog" );
// Creates and initializes a new Queue.
Queue myQueue = new Queue();
myQueue.Enqueue( "quick" );
myQueue.Enqueue( "brown" );
// Displays the ArrayList and the Queue.
Console.WriteLine( "The ArrayList initially contains the following:" );
PrintValues( myAL );
Console.WriteLine( "The Queue initially contains the following:" );
PrintValues( myQueue );
// Copies the Queue elements to the ArrayList at index 1.
myAL.InsertRange( 1, myQueue );
// Displays the ArrayList.
Console.WriteLine( "After adding the Queue, the ArrayList now contains:" );
PrintValues( myAL );
// Search for "dog" and add "lazy" before it.
myAL.Insert( myAL.IndexOf( "dog" ), "lazy" );
// Displays the ArrayList.
Console.WriteLine( "After adding \"lazy\", the ArrayList now contains:" );
PrintValues( myAL );
// Add "!!!" at the end.
myAL.Insert( myAL.Count, "!!!" );
// Displays the ArrayList.
Console.WriteLine( "After adding \"!!!\", the ArrayList now contains:" );
PrintValues( myAL );
// Inserting an element beyond Count throws an exception.
try {
myAL.Insert( myAL.Count+1, "anystring" );
} catch ( Exception myException ) {
Console.WriteLine("Exception: " + myException.ToString());
}
}
public static void PrintValues( IEnumerable myList ) {
foreach ( Object obj in myList )
Console.Write( " {0}", obj );
Console.WriteLine();
}
}
/*
This code produces the following output.
The ArrayList initially contains the following:
The fox jumps over the dog
The Queue initially contains the following:
quick brown
After adding the Queue, the ArrayList now contains:
The quick brown fox jumps over the dog
After adding "lazy", the ArrayList now contains:
The quick brown fox jumps over the lazy dog
After adding "!!!", the ArrayList now contains:
The quick brown fox jumps over the lazy dog !!!
Exception: System.ArgumentOutOfRangeException: Insertion index was out of range. Must be non-negative and less than or equal to size.
Parameter name: index
at System.Collections.ArrayList.Insert(Int32 index, Object value)
at SamplesArrayList.Main()
*/
using namespace System;
using namespace System::Collections;
void PrintValues( IEnumerable^ myList );
int main()
{
// Creates and initializes a new ArrayList using Insert instead of Add.
ArrayList^ myAL = gcnew ArrayList;
myAL->Insert( 0, "The" );
myAL->Insert( 1, "fox" );
myAL->Insert( 2, "jumps" );
myAL->Insert( 3, "over" );
myAL->Insert( 4, "the" );
myAL->Insert( 5, "dog" );
// Creates and initializes a new Queue.
Queue^ myQueue = gcnew Queue;
myQueue->Enqueue( "quick" );
myQueue->Enqueue( "brown" );
// Displays the ArrayList and the Queue.
Console::WriteLine( "The ArrayList initially contains the following:" );
PrintValues( myAL );
Console::WriteLine( "The Queue initially contains the following:" );
PrintValues( myQueue );
// Copies the Queue elements to the ArrayList at index 1.
myAL->InsertRange( 1, myQueue );
// Displays the ArrayList.
Console::WriteLine( "After adding the Queue, the ArrayList now contains:" );
PrintValues( myAL );
// Search for "dog" and add "lazy" before it.
myAL->Insert( myAL->IndexOf( "dog" ), "lazy" );
// Displays the ArrayList.
Console::WriteLine( "After adding \"lazy\", the ArrayList now contains:" );
PrintValues( myAL );
// Add "!!!" at the end.
myAL->Insert( myAL->Count, "!!!" );
// Displays the ArrayList.
Console::WriteLine( "After adding \"!!!\", the ArrayList now contains:" );
PrintValues( myAL );
// Inserting an element beyond Count throws an exception.
try
{
myAL->Insert( myAL->Count + 1, "anystring" );
}
catch ( Exception^ myException )
{
Console::WriteLine( "Exception: {0}", myException );
}
}
void PrintValues( IEnumerable^ myList )
{
IEnumerator^ myEnum = myList->GetEnumerator();
while ( myEnum->MoveNext() )
{
Object^ obj = safe_cast<Object^>(myEnum->Current);
Console::Write( " {0}", obj );
}
Console::WriteLine();
}
/*
This code produces the following output.
The ArrayList initially contains the following:
The fox jumps over the dog
The Queue initially contains the following:
quick brown
After adding the Queue, the ArrayList now contains:
The quick brown fox jumps over the dog
After adding "lazy", the ArrayList now contains:
The quick brown fox jumps over the lazy dog
After adding "!!!", the ArrayList now contains:
The quick brown fox jumps over the lazy dog !!!
Exception: System.ArgumentOutOfRangeException: Insertion index was out of range. Must be non-negative and less than or equal to size.
Parameter name: index
at System.Collections.ArrayList.Insert(Int32 index, Object value)
at SamplesArrayList.Main()
*/
import System.*;
import System.Collections.*;
public class SamplesArrayList
{
public static void main(String[] args)
{
// Creates and initializes a new ArrayList using Insert instead of Add.
ArrayList myAL = new ArrayList();
myAL.Insert(0, "The");
myAL.Insert(1, "fox");
myAL.Insert(2, "jumps");
myAL.Insert(3, "over");
myAL.Insert(4, "the");
myAL.Insert(5, "dog");
// Creates and initializes a new Queue.
Queue myQueue = new Queue();
myQueue.Enqueue("quick");
myQueue.Enqueue("brown");
// Displays the ArrayList and the Queue.
Console.WriteLine("The ArrayList initially contains the following:");
PrintValues(myAL);
Console.WriteLine("The Queue initially contains the following:");
PrintValues(myQueue);
// Copies the Queue elements to the ArrayList at index 1.
myAL.InsertRange(1, myQueue);
// Displays the ArrayList.
Console.WriteLine("After adding the Queue, the ArrayList now contains:");
PrintValues(myAL);
// Search for "dog" and add "lazy" before it.
myAL.Insert(myAL.IndexOf("dog"), "lazy");
// Displays the ArrayList.
Console.WriteLine("After adding \"lazy\", the ArrayList now contains:");
PrintValues(myAL);
// Add "!!!" at the end.
myAL.Insert(myAL.get_Count(), "!!!");
// Displays the ArrayList.
Console.WriteLine("After adding \"!!!\", the ArrayList now contains:");
PrintValues(myAL);
// Inserting an element beyond Count throws an exception.
try {
myAL.Insert(myAL.get_Count() + 1, "anystring");
}
catch (System.Exception myException) {
Console.WriteLine("Exception: " + myException.ToString());
}
} //main
public static void PrintValues(IEnumerable myList)
{
IEnumerator objMyEnum = myList.GetEnumerator();
while (objMyEnum.MoveNext()) {
Object obj = objMyEnum.get_Current();
Console.Write(" {0}", obj);
}
Console.WriteLine();
} //PrintValues
} //SamplesArrayList
/*
This code produces the following output.
The ArrayList initially contains the following:
The fox jumps over the dog
The Queue initially contains the following:
quick brown
After adding the Queue, the ArrayList now contains:
The quick brown fox jumps over the dog
After adding "lazy", the ArrayList now contains:
The quick brown fox jumps over the lazy dog
After adding "!!!", the ArrayList now contains:
The quick brown fox jumps over the lazy dog !!!
Exception: System.ArgumentOutOfRangeException: Insertion index was out of range.
Must be non-negative and less than or equal to size.
Parameter name: index
at System.Collections.ArrayList.Insert(Int32 index, Object value)
at SamplesArrayList.main(String[] args)
*/
import System;
import System.Collections;
// Creates and initializes a new ArrayList using Insert instead of Add.
var myAL : ArrayList = new ArrayList();
myAL.Insert( 0, "The" );
myAL.Insert( 1, "fox" );
myAL.Insert( 2, "jumped" );
myAL.Insert( 3, "over" );
myAL.Insert( 4, "the" );
myAL.Insert( 5, "dog" );
// Creates and initializes a new Queue.
var myQueue : Queue = new Queue();
myQueue.Enqueue( "quick" );
myQueue.Enqueue( "brown" );
// Displays the ArrayList and the Queue.
Console.WriteLine( "The ArrayList initially contains the following:" );
PrintValues( myAL );
Console.WriteLine( "The Queue initially contains the following:" );
PrintValues( myQueue );
// Copies the Queue elements to the ArrayList at index 1.
myAL.InsertRange( 1, myQueue );
// Displays the ArrayList.
Console.WriteLine( "After adding the Queue, the ArrayList now contains:" );
PrintValues( myAL );
// Search for "dog" and add "lazy" before it.
myAL.Insert( myAL.IndexOf( "dog" ), "lazy" );
// Displays the ArrayList.
Console.WriteLine( "After adding \"lazy\", the ArrayList now contains:" );
PrintValues( myAL );
// Add "!!!" at the end.
myAL.Insert( myAL.Count, "!!!" );
// Displays the ArrayList.
Console.WriteLine( "After adding \"!!!\", the ArrayList now contains:" );
PrintValues( myAL );
// Inserting an element beyond Count throws an exception.
try {
myAL.Insert( myAL.Count+1, "anystring" );
} catch ( myException : Exception ) {
Console.WriteLine("Exception: " + myException.ToString());
}
function PrintValues( myList : IEnumerable) {
var myEnumerator : System.Collections.IEnumerator = myList.GetEnumerator();
while ( myEnumerator.MoveNext() )
Console.Write( "\t{0}", myEnumerator.Current );
Console.WriteLine();
}
/*
This code produces the following output.
The ArrayList initially contains the following:
The fox jumped over the dog
The Queue initially contains the following:
quick brown
After adding the Queue, the ArrayList now contains:
The quick brown fox jumped over the dog
After adding "lazy", the ArrayList now contains:
The quick brown fox jumped over the lazy dog
After adding "!!!", the ArrayList now contains:
The quick brown fox jumped over the lazy dog !!!
Exception: System.ArgumentOutOfRangeException: Insertion index was out of range. Must be non-negative and less than or equal to size.
Parameter name: index
at System.Collections.ArrayList.Insert(Int32 index, Object value)
at JScript 0.Global Code()
*/
平台
Windows 98、Windows 2000 SP4、Windows CE、Windows Millennium Edition、Windows Mobile for Pocket PC、Windows Mobile for Smartphone、Windows Server 2003、Windows XP Media Center Edition、Windows XP Professional x64 Edition、Windows XP SP2、Windows XP Starter Edition
.NET Framework 并不是对每个平台的所有版本都提供支持。有关受支持版本的列表,请参见系统要求。
版本信息
.NET Framework
受以下版本支持:2.0、1.1、1.0
.NET Compact Framework
受以下版本支持:2.0、1.0
请参见
参考
ArrayList 类
ArrayList 成员
System.Collections 命名空间
InsertRange
Add
Remove