Differences between LINQ Concat Union intersect

Concat: concatenates two sequences. Http://msdn.microsoft.com/zh-cn/library/bb351755 (V = vs.90). aspx

Union: generate the union of two sequences by using the default equal comparator. Http://msdn.microsoft.com/zh-cn/library/bb341731 (V = vs.90). aspx

Intersect: the intersection of two sequences is generated by comparing values using the default equal comparator. Http://msdn.microsoft.com/zh-cn/library/bb460136 (V = vs.90). aspx

It can be understood as follows:

Assume there are two sequences:

VaR A = new list <int> {1, 1, 2, 3, 4 };
VaR B = new list <int> {4, 5, 5, 6, 7 };

A. Concat (B) means to concatenate sequence a and sequence B to create a new sequence without removing duplicates;

A. Union (B) indicates concatenating sequence a and sequence B, removing duplicates, and creating a new sequence;

While a. Intersect (B) only takes the same part (intersection) of Series A and Series B to create a new sequence.

ExampleCode:

Void main ()
{
VaR A = new list <int> {1, 1, 2, 3, 4 };
VaR B = new list <int> {4, 5, 5, 6, 7 };

Print (A. Concat (B). tolist ());
Print (A. Union (B). tolist ());
Print (A. Intersect (B). tolist ());

/*
* ******* A. Concat (B )************
1
1
2
3
4
4
5
5
6
7
*********************************

* ******** A. Union (B )***********
1
2
3
4
5
6
7
*********************************

* ******** A. Intersect (B )***********
4
*********************************
*/
}