Dictionary<TKey,TValue>.Remove 方法
定义
重载
Remove(TKey) |
从 Dictionary<TKey,TValue> 中移除所指定的键的值。Removes the value with the specified key from the Dictionary<TKey,TValue>. |
Remove(TKey, TValue) |
从 Dictionary<TKey,TValue> 中删除具有指定键的值,并将元素复制到 |
Remove(TKey)
从 Dictionary<TKey,TValue> 中移除所指定的键的值。Removes the value with the specified key from the Dictionary<TKey,TValue>.
public:
virtual bool Remove(TKey key);
public bool Remove (TKey key);
abstract member Remove : 'Key -> bool
override this.Remove : 'Key -> bool
Public Function Remove (key As TKey) As Boolean
参数
- key
- TKey
要移除的元素的键。The key of the element to remove.
返回
如果成功找到并移除该元素,则为 true
;否则为 false
。true
if the element is successfully found and removed; otherwise, false
. 如果在 Dictionary<TKey,TValue> 中没有找到 key
,则此方法返回 false
。This method returns false
if key
is not found in the Dictionary<TKey,TValue>.
实现
例外
key
上声明的默认值为 null
。key
is null
.
示例
下面的代码示例演示如何使用方法从字典中移除键/值对 Remove 。The following code example shows how to remove a key/value pair from a dictionary using the Remove method.
此代码示例是为类提供的更大示例的一部分 Dictionary<TKey,TValue> (openWith
是此示例中使用的字典的名称) 。This code example is part of a larger example provided for the Dictionary<TKey,TValue> class (openWith
is the name of the Dictionary used in this example).
// Use the Remove method to remove a key/value pair.
Console::WriteLine("\nRemove(\"doc\")");
openWith->Remove("doc");
if (!openWith->ContainsKey("doc"))
{
Console::WriteLine("Key \"doc\" is not found.");
}
// Use the Remove method to remove a key/value pair.
Console.WriteLine("\nRemove(\"doc\")");
openWith.Remove("doc");
if (!openWith.ContainsKey("doc"))
{
Console.WriteLine("Key \"doc\" is not found.");
}
' Use the Remove method to remove a key/value pair.
Console.WriteLine(vbLf + "Remove(""doc"")")
openWith.Remove("doc")
If Not openWith.ContainsKey("doc") Then
Console.WriteLine("Key ""doc"" is not found.")
End If
注解
如果不 Dictionary<TKey,TValue> 包含具有指定键的元素,则将 Dictionary<TKey,TValue> 保持不变。If the Dictionary<TKey,TValue> does not contain an element with the specified key, the Dictionary<TKey,TValue> remains unchanged. 不引发异常。No exception is thrown.
此方法使用 O (1) 操作。This method approaches an O(1) operation.
仅限 .NET Core 3.0 +:可以安全地调用此转变方法,而不会对实例上的活动枚举器无效 Dictionary<TKey,TValue> 。.NET Core 3.0+ only: this mutating method may be safely called without invalidating active enumerators on the Dictionary<TKey,TValue> instance. 这并不意味着线程安全。This does not imply thread safety.
另请参阅
适用于
Remove(TKey, TValue)
从 Dictionary<TKey,TValue> 中删除具有指定键的值,并将元素复制到 value
参数。Removes the value with the specified key from the Dictionary<TKey,TValue>, and copies the element to the value
parameter.
public:
bool Remove(TKey key, [Runtime::InteropServices::Out] TValue % value);
public bool Remove (TKey key, out TValue value);
member this.Remove : 'Key * 'Value -> bool
Public Function Remove (key As TKey, ByRef value As TValue) As Boolean
参数
- key
- TKey
要移除的元素的键。The key of the element to remove.
- value
- TValue
已删除的元素。The removed element.
返回
如果成功找到并移除该元素,则为 true
;否则为 false
。true
if the element is successfully found and removed; otherwise, false
.
例外
key
上声明的默认值为 null
。key
is null
.