c#数据绑定之linq使用实例

XAML：














Button1 　LINQ TO ENTITY
using (var context = new AdventureWorks2008Entities())
{
//var people = context.People.Where(c => c.LastName == "King").OrderBy(d => d.FirstName).Select(r => new { r.FirstName,r.LastName});
//var people = context.People.Where(c => c.LastName == "King").OrderBy(c =>c.FirstName).Select(c => new { c.FirstName, c.LastName });
var people = from per in context.People
//join emp in context.Employees on per.BusinessEntityID equals emp.BusinessEntityID
where per.LastName == "King"
orderby per.FirstName
select new { per.FirstName, per.LastName};
foreach (var person in people)
{
listBox1.Items.Add(string.Format("{0} t t {1} ", person.FirstName, person.LastName));
}
}
Button2 LINQ TO ENTITYSQL
using (var context = new AdventureWorks2008Entities())
{
var str = "SELECT VALUE p FROM AdventureWorks2008Entities.People AS p WHERE p.LastName= @LastName Order by p.FirstName";
//var people = context.CreateQuery(str);
var people = new System.Data.Objects.ObjectQuery(str, context);
people.Parameters.Add(new System.Data.Objects.ObjectParameter("LastName", "King"));
foreach (var person in people)
{
listBox2.Items.Add(string.Format("{0} t t{1}", person.FirstName, person.LastName));
}
}
Button3 LINQ TO ENTITYCLIENT
var firstName = "";
var lastName = "";
using (EntityConnection conn = new EntityConnection("name=AdventureWorks2008Entities"))
{
string str = "SELECT p.FirstName, p.LastName FROM AdventureWorks2008Entities.People AS p WHERE p.LastName='King' Order by p.FirstName";
conn.Open();
EntityCommand cmd = conn.CreateCommand();
cmd.CommandText =str;
using (EntityDataReader rdr = cmd.ExecuteReader(System.Data.CommandBehavior.SequentialAccess))
{
while (rdr.Read())
{
firstName = rdr.GetString(0);
lastName = rdr.GetString(1);
listBox3.Items.Add(string.Format("{0}t t{1}", firstName, lastName));
}
}
conn.Close();
}
}