The Hashtable class represents a collection of key-and-value pairs that are organized based on the hash code of the key. The key is used to access the items in the collection. Hashtable.ContainsKey(Object) Method is used to check whether the Hashtable contains a specific key or not.
public virtual bool ContainsKey(object key);
key: The key of type System.Object to locate in the Hashtable.
Return Type: It return true if the Hashtable contains an element with the specified key otherwise, false. The return type of this method is System.Boolean.
Exception: This method can give ArgumentNullException if the key is null.
Below given are some examples to understand the implementation in a better way:
myTable contains the key
myTable doesn't contain the key
- C# | Check whether a Hashtable contains a specific key or not
- 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 the HybridDictionary for a specific key
- C# | Check if ListDictionary contains a specific key
- C# | Check if the StringDictionary contains a specific key
- C# | Check if the StringDictionary contains a specific value
- C# | Check if a SortedList object contains a specific value
- C# | Check if OrderedDictionary collection contains a specific key
- C# | Check if the SortedSet contains a specific element
- C# | Check whether a SortedList object contains a specific key
- C# | Get or Set the value associated with specified key in Hashtable
- C# Hashtable with Examples
- C# | Hashtable Class
- C# | Gets an ICollection containing the values in the Hashtable
- C# | Gets an ICollection containing the keys in the Hashtable
- C# | How to get hash code for the specified key of a Hashtable
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