//遍历窗体所有控件，

foreach (Control control in this.Controls)

{
    //遍历后的操作...

    control.Enabled = false;

}

foreach (Control control in this.panel4.Controls)

{

    control.Enabled = false;

}

foreach (Control control in this.Controls)

{
　　//遍历所有TextBox...

    if (control is TextBox)

    {

        TextBox t = (TextBox)control;

        t.Enabled = false;

    }
　　//遍历所有DateTimePicker...

    if (control is DateTimePicker)

    {

        DateTimePicker d = (DateTimePicker)control;

        d.Enabled = false;

    }

}