js swith case
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"> <html xmlns="http://www.w3.org/1999/xhtml" > <head> <title>范例 5-4</title> </head> <body> <script language="javascript"> var who = "Bob"; // 当前来人是Bob switch( who ) // 使用开头语句,控制对每个人的问候,以致于不问错对象 { case "Bob": alert( "Hello," + who ); break; case "Jim": alert( "Hello," + who ); break; case "Tom": alert( "Hello," + who ); break; default: alert( "Nobody~!"); } </script> </body> </html>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"> <html xmlns="http://www.w3.org/1999/xhtml" > <head> <title>范例 5-5</title> </head> <body id="PageBody" style="background:red"><!--设定body节点的ID,以便在JavaScript代码中操作--> <script language="javascript"> function ChangeBgColor( colorIndex ) { var dombody = document.getElementById( "PageBody" ); // 获取body节点 if( dombody == null ) // 如果没有body节点将直接返回 { return; } else // body节点成功获取 { switch( colorIndex ) // 使用多路开关语句根据菜单传入的值更改网页背景 { case 1: dombody.style.background = "#666666"; // 通过设定style元素的background属性以改变背景 break; case 2: dombody.style.background = "#003333"; break; case 3: dombody.style.background = "#ccccff"; break; case 4: dombody.style.background = "#6699cc"; break; default: dombody.style.background = "white"; // break; } } } </script> <!--各颜色菜单,用户点击菜单时,背景颜色将变为与菜单相同的颜色--> <div style="width: 100px; height: 20px; text-align:center; background-color: #666666;" onclick="return ChangeBgColor( 1 )"> </div> <div style="width: 100px; height: 20px; text-align:center; background-color: #003333;" onclick="return ChangeBgColor( 2 )"> </div> <div style="width: 100px; height: 20px; text-align:center; background-color: #ccccff;" onclick="return ChangeBgColor( 3 )"> </div> <div style="width: 100px; height: 20px; text-align:center; background-color: #6699cc;" onclick="return ChangeBgColor( 4 )"> </div> </body> </html>