如何在后台代码中设置和获取用户控件中的子控件的属性？

>>>1、如何在后台代码中设置和获取用户控件中的子控件的属性？

add public properties/methods in your codebehind class for your usercontrol and declare in your page class:

protected YourUserControlCodeBehindClass YourUserControlID;

..

if you don't have a codebehind class, you can always do

UserControl c = (UserControl)FindControl("YourUserControlID");

TextBox tb = (TextBox) c.FindControl("YourTextBoxIDInYourUserControl);
tb.Text = "123";

>>>2、如何在后台设置和获取用户控件本身的属性？

if you have a codebehind class for your usercontrol, you can do
protected YourUserControlCodeBehindClass YourUserControlID;

YourUserControlID.Property1 = "123";

otherwise, you have to use Reflection