List
列表的属性:
- 它与数组不同。列表可以动态调整大小,但数组则不能。
- 列表类可以接受null作为引用类型的有效值,并且还允许重复的元素。
- 如果Count等于Capacity,则List的容量会通过重新分配内部数组自动增加。在添加新元素之前,现有元素将被复制到新数组。
句法:
public void AddRange (System.Collections.Generic.IEnumerable collection);
范围:
collection: It is the specified collection whose elements will be added to the end of the List
异常:如果集合为null,则此方法将提供ArgumentNullException。
注意:集合本身不能为null,但是如果类型T是引用类型,则它可以包含为null的元素。集合中元素的顺序始终保留在List
下面的程序说明了上面讨论的方法的使用:
范例1:
// C# program to illustrate the
// List.AddRange Method
using System;
using System.Collections.Generic;
class Geeks {
// Main Method
public static void Main(String[] args)
{
// Creating a List of Strings
List firstlist = new List();
// adding elements in firstlist
firstlist.Add("Geeks");
firstlist.Add("GFG");
firstlist.Add("C#");
firstlist.Add("Tutorials");
Console.WriteLine("Before AddRange Method");
Console.WriteLine();
// displaying the item of List
foreach(String str in firstlist)
{
Console.WriteLine(str);
}
Console.WriteLine("\nAfter AddRange Method\n");
// Here we are using AddRange method
// Which adds the elements of firstlist
// Collection in firstlist again i.e.
// we have copied the whole firstlist
// in it
firstlist.AddRange(firstlist);
// displaying the item of List
foreach(String str in firstlist)
{
Console.WriteLine(str);
}
}
}
输出:
Before AddRange Method
Geeks
GFG
C#
Tutorials
After AddRange Method
Geeks
GFG
C#
Tutorials
Geeks
GFG
C#
Tutorials
范例2:
// C# program to illustrate the
// List.AddRange Method
using System;
using System.Collections.Generic;
class Geeks {
// Main Method
public static void Main(String[] args)
{
// Creating a List of Strings
List firstlist = new List();
// adding elements in firstlist
firstlist.Add("Geeks");
firstlist.Add("GFG");
firstlist.Add("C#");
firstlist.Add("Tutorials");
Console.WriteLine("Before AddRange Method");
Console.WriteLine();
// displaying the item of List
foreach(String str in firstlist)
{
Console.WriteLine(str);
}
Console.WriteLine("\nAfter AddRange Method\n");
// taking array of String
string[] str_add = { "Collections",
"Generic",
"List" };
// here we are adding the elements
// of the str_add to the end of
// the List.
firstlist.AddRange(str_add);
// displaying the item of List
foreach(String str in firstlist)
{
Console.WriteLine(str);
}
}
}
输出:
Before AddRange Method
Geeks
GFG
C#
Tutorials
After AddRange Method
Geeks
GFG
C#
Tutorials
Collections
Generic
List
参考:
- https://docs.microsoft.com/zh-cn/dotnet/api/system.collections.generic.list-1.addrange?view=netframework-4.7.2