说明：  点击form1窗体上的comboBox下拉列表框然后弹出一个form2窗体，form2窗体上有一个dataGridView1，然后双击dataGriidView1的某一行数据，会把选中的该行数据传递到fform1，并自动填充form1中的comboBox与textbox. form2窗体中的主要事件
(ComboBox drop-down list box, click on the form1 form and then pop up a form2 form, form2 form a dataGridView1, and then double-click a line of data dataGriidView1, will select the row of data is passed to the fform1 and automatically fill the form1 major events in the comboBox with the textbox. form2 form)