console 命令行工具 X clear

console

function setFocus()
  {
  document.getElementById('text1').focus()
  }
function loseFocus()
  {
  document.getElementById('text1').blur()
  }

<form> 
  <input type="text" id="text1"> 
  <br> 
  <input type="button" onclick="setFocus()" value="设置焦点"> 
  <input type="button" onclick="loseFocus()" value="失去焦点"> 
 </form>