C# | OrderedDictionary.Item [Object] Property

The OrderedDictionary.Item [Object] property in C# is used to get or set the value at the specified key in the OrderedDictionary. The key is specified as an Object type, and the value is returned or set as an Object type.

Syntax

public virtual Object this[Object key] { get; set; }

The this keyword refers to the current instance of the class, while the square brackets with the Object parameter indicate an index. The get and set keywords indicate whether the property can be read from or written to.

Example

OrderedDictionary dict = new OrderedDictionary();
dict.Add("key1","value1");
dict.Add("key2","value2");

//accessing value using the Item property
Object val1 = dict["key1"]; 
Object val2 = dict[1]; //equivalent to dict["key2"]

//setting value using the Item property
dict["key1"] = "new value";

In the above example, we create a new OrderedDictionary, add two key-value pairs to it using the Add() method, and then access the values using the Item property by passing the keys as Object parameters. We can also set a new value at a particular key using the same property.

Remarks

The OrderedDictionary class provides a way to access its elements in the same order in which they were added. Its Item property allows us to retrieve or set a value at a particular key.

While using the Item property, we need to ensure that the key passed as an Object parameter matches the actual key type used to add the value to the dictionary, else it will throw an error at runtime.

If an attempt is made to get or set a value at a non-existent key through the Item property, it will throw an ArgumentException.

Conclusion

In C#, the OrderedDictionary.Item [Object] property provides a way to get or set a value at a particular key in an OrderedDictionary. It can be used to retrieve the value for a given key or set a new value at a specific key.