类型:文本输入框，点击回车，输入类型:文本消失。

<input name='Header1$txbsearch' type='text' value='18912345678' id='Header1_txbsearch' onfocus='if (value =='18912345678'){value =''}' onblur='if (value ==''){value='18912345678'}' style='color:#999999;' />