c#数据绑定之linq使用示例

xaml：

<grid>
            <grid.columndefinitions>
                <columndefinition width="2*"/>
                <columndefinition width="8*"/>
            </grid.columndefinitions>
            <grid.rowdefinitions>
                <rowdefinition />
                <rowdefinition />
                <rowdefinition  />
            </grid.rowdefinitions>
            <listbox grid.column="1"  margin="10" name="listbox1"  />
            <button content="linqtoentity" grid.column="0" margin="5" name="button1" click="button1_click" />
            <listbox grid.column="1" grid.row="1"  margin="10" name="listbox2"  />
            <button content="linqtosql" grid.column="0" grid.row="1" margin="5" name="button2" click="button2_click" />
            <listbox grid.column="1" grid.row="2"  margin="10" name="listbox3"  />
            <button content="lintoenclient" grid.column="0" grid.row="2" margin="5" name="button3" click="button3_click"  />
        </grid>

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<person>(str);
                var people = new system.data.objects.objectquery<person>(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();
            }
        }