LINQ Single and SingleOrDefault

Single means you are expecting only one result from LINQ query. If you get more than one or zero matches, then it throws exception.

SingleOrDefault means if you get single result, it returns that result but if it doesn't find any matches it returns default value but you will not get any exception.

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Return only one result from LINQ Query

You can do it in two ways, either use First or use Single.

First returns only first row, even there are multiple rows

Single expects only one row to be returned, and if there are multiple rows, it throws exception.

So, use Single if you are expecting only one row to be returned.

EX: var book= from book in store where (book.price > 100) select book).First();
Generally , the query returns all books having price greater than 100. but , as we are using  " .First() " only first book will be returned.

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return more than one value from a method

We can't return more than one values from a method.

An alternative way would be, add all those values to be returned into  Array and return that array.

Ex: public int[] returnArray ()
{
int[] myArray=new int[3];
myArray[0] = value1;
myArray[1] = value2;
myArray[2] = value3;

      return myArray;
}

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