鼠标onfocus或onblur效果

onfocus onblur

   
     

    
      
    
      <
    
      input type
    
      =
    
      "
    
      text
    
      "
    
       name
    
      =
    
      ""
    
       value
    
      =
    
      "
    
      我是一个兵
    
      "
    
       id
    
      =
    
      "
    
      test
    
      "
    
       
    
      /
    
      >
    
      

    
      

    
      <
    
      script type
    
      =
    
      "
    
      text/javascript
    
      "
    
      >
    
      

    
      var
    
       test 
    
      =
    
       document.getElementById(
    
      "
    
      test
    
      "
    
      );
test.onfocus 
    
      =
    
       
    
      function
    
      (){ 
    
      if
    
      (
    
      this
    
      .value 
    
      ==
    
       
    
      this
    
      .defaultValue) 
    
      this
    
      .value
    
      =
    
      ""
    
      ;}
test.onblur 
    
      =
    
       
    
      function
    
      (){ 
    
      this
    
      .value 
    
      =
    
       
    
      this
    
      .value 
    
      ==
    
       
    
      0
    
       
    
      ?
    
       
    
      this
    
      .defaultValue : 
    
      this
    
      .value;}

    
      <
    
      /
    
      script>