Simple LINQ notes

Only. Net 3.5 is used for LINQ.

To introduce the namespace system. LINQ.

To introduce system. xml. LINQ to XML

To introduce system. Data. LINQ to ADO. net

Each LINQ query starts with a from clause. In a LINQ query, the Select clause and select clause are both mandatory clauses.

Must end with a select or group clause

The from clause includes two basic functions.

-- 1> specify the data source to be collected for query

-- 2> define a local variable to indicate a single element in the data source.

1. The simplest query command

Static void main (string [] ARGs) {int [] ary = {, 9 }; // define the array var query1 = from C in ary // define the query statement select C; foreach (VAR item in query1) {console. write (item);} console. readkey ();}

Output

2. Specify the Data Type query for the local variable, for example, specify the object type

1 int [] ary = {, 9 }; // define the array 2 var query1 = 3 from object C in ary // define the query statement 4 select C;

 

Simple LINQ notes