Hashtable.Contains(Object) Method is used to check whether the Hashtable contains a specific key or not.
public virtual bool Contains (object key);
Here, key is the Key of Object type which is to be located in the Hashtable.
Return Value: This method returns true if the Hashtable contains an element with the specified key otherwise returns false.
Exception: This method will give ArgumentNullException if the key is null.
- Hashtable.ContainsKey(Object) Method is also used to check whether the Hashtable contains a specific key or not. This method behaves same as Contains() method.
- Contains method implements IDictionary.Contains. It behaves exactly as ContainsKey and this method is an O(1) operation.
Below programs illustrate the use of above-discussed method:
System.ArgumentNullException: Key cannot be null.
Parameter name: key
- C# | Check if the Hashtable contains a specific Key
- C# | Check if the Hashtable contains a specific Value
- C# | Check if a Hashtable is equal to another Hashtable
- C# | Check if Hashtable is read-only
- C# | Check if Hashtable has a fixed size
- C# | Check if Hashtable is synchronized (thread safe)
- C# | Check if the StringDictionary contains a specific key
- C# | Check if ListDictionary contains a specific key
- C# | Check the HybridDictionary for a specific key
- C# | Check if the StringDictionary contains a specific value
- C# | Check if the SortedSet contains a specific element
- C# | Check if a SortedList object contains a specific value
- C# | Check if OrderedDictionary collection contains a specific key
- C# | Check whether a SortedList object contains a specific key
- C# | Get or Set the value associated with specified key in Hashtable
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