KeyPress event in ComboBox

Hi,

I am working on Combobox.

I need to search by typing the character in the combobox by using linq.

I am using a gridview to display the data fro a table.

i have written the following code under ComboBox_KeyPres event

{

string combotext = comboBox1.Text;

dataGridView1.DataSource = from em in dc.emps where em.dept.Contains(combotext ) select em;

}

once i enter the character like 'A','D' etc the value is not getting stored in the variable Combotext.

after the keypress event is completed the value is getting stored into the variable.

I want the value to stored immediately after entering it into the Combobox.

Thank you