Dictionary<TKey,TValue>.Remove 方法

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

返回

Boolean

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

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

• Add(TKey, TValue)
• Remove(TKey)

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

返回

Boolean

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