How to Convert an Array Into a Generic Type in C#

Look the parameter this method expects. The first parameter expects a key and the second parameter expects a value and as we know a dictionary is a collection of key/value pairs. So, we need to pass the name of the object from where this dictionary will get the key and the value and for that we will use a lambda expression.

Now look at the return type of this ToDictionary method.

It is returning a dictionary object back and look at the type of the key/value pair <int, Student> which means we can create an object of that type and store that data we got from the ToDictionary method.

The next step is to retrieve the student details from this StudentDictionary object and for that we can use a foreach loop.

As we know a dictionary is a collection of key/value pairs. So, we can say:

foreach (KeyValuePair<int, Student> student in StudentDictionary) {  
}

Because the dictionary object will return a key and the value back.

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Convert Dictionary to an Array

To convert a dictionary to an array, we can use the ToArray extension method. But before converting the dictionary collection into an array, first we need to retrieve the values from the collection of the dictionary object and for that we can use the Values property and on that property we can invoke the ToArray method.

To get all the student details we can use a foreach loop.

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Convert List to a Dictionary

In the topic Convert Array to List, we have created a StudentList student object. Let's see how to convert this StudentList into a dictionary.

To convert a list into a dictionary, we can use the ToDictionary method.

In the first parameter of this ToDictionary method, we need to pass the object from where we will get the key and in the second parameter we need to pass the object from where we will get the value.

Based on the key/value we pass in as the parameter argument, the return type of ToDictionary is assigned and here it returns a dictionary object of <int, Student>. So, we can create an object that type and store the data.

To get all the student details from this dictionary object, we can use a foreach loop.

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Convert Dictionary to a List

To convert a dictionary into a list, we can use the ToList method. In the topic Convert an array to a Dictionary we have created a StudentDictionary object. So, let' see how to convert that object into a list.

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I hope you like this. Thank you.