js控制表单操作的常用代码小结

  1.鼠标经过时自动选择文本

  Code:

  

复制代码 代码如下:

  鼠标划过自动选中:<input type="text" value="默认值" onMouseOver="this.focus();" onfucus="this.seelct()" />

  2.设置单选按钮

  Code:

  

复制代码 代码如下:

  <html>

  <head>

  <meta http-equiv="Content-Type" content="text/html; charset=utf-8" />

  <meta name="viewport" content="initial-scale=1.0, user-scalable=no" />

  <title>js操作表单</title>

  <script language="javascript">

  function getChoice(){

  var oForm=document.forms["myForm1"];

  var aChoice=oForm.camera;

  for(i=0;i<aChoice.length;i++)

  if(aChoice[i].checked)

  break;

  alert("您使用的相机品牌是:"+aChoice[i].value);

  }

  function setChoice(iNum){

  var oForm=document.forms["myForm1"];

  oForm.camera[iNum].checked=true;

  }

  </script>

  </head>

  <body>

  <form method="post" name="myForm1" action="">

  <p>您使用的相机品牌</p>

  <p>

  <input type="radio" name="camera" id="canon" value="Canon">

  <label for="canon">Canon</label>

  </p>

  <p>

  <input type="radio" name="camera" id="nikon" value="Nikon">

  <label for="nikon">Nikon</label>

  </p>

  <p>

  <input type="radio" name="camera" id="sony" value="Sony">

  <label for="sony">Sony</label>

  </p>

  <p>

  <input type="radio" name="camera" id="pentax" value="Tentax">

  <label for="pentax">Tentax</label>

  </p>

  <p>

  <input type="button" value="检查选中对象" onClick="getChoice();">

  <input type="button" value="设置为Canon" onClick="setChoice(0);">

  </p>

  </form>

  </body>

  </html>

  3.设置复选框

  Code:

  

复制代码 代码如下:

  <html>

  <head>

  <meta http-equiv="Content-Type" content="text/html; charset=utf-8" />

  <meta name="viewport" content="initial-scale=1.0, user-scalable=no" />

  <title>js操作表单</title>

  <script language="javascript">

  function changeBoxes(action){

  var oForm=document.forms["myForm1"];

  var oCheckBox=oForm.hobby;

  for(var i=0;i<oCheckBox.length;i++)//遍历每一个选项

  if(action<0) //反选

  oCheckBox[i].checked=!oCheckBox[i].checked;

  else

  oCheckBox[i].checked=action;

  }

  </script>

  </head>

  <body>

  <form method="post" name="myForm1" action="">

  <p>

  <input type="checkbox" name="hobby" id="ball" value="ball">

  <label for="ball">打球</label>

  </p>

  <p>

  <input type="checkbox" name="hobby" id="TV" value="TV">

  <label for="TV">看电视</label>

  </p>

  <p>

  <input type="checkbox" name="hobby" id="net" value="net">

  <label for="net">上网</label>

  </p>

  <p>

  <input type="checkbox" name="hobby" id="book" value="book">

  <label for="book">看书</label>

  </p>

  <p>

  <input type="checkbox" name="hobby" id="run" value="run">

  <label for="run">跑步</label>

  </p>

  <p>

  <input type="button" value="全选" onClick="changeBoxes(1);">

  <input type="button" value="全不选" onClick="changeBoxes(0);"/>

  <input type="button" value="反选" onClick="changeBoxes(-1);"/>

  </p>

  </form>

  </body>

  </html>

  4.设置下拉菜单

  下拉菜单中最重要的莫过于访问被用户选中的选项,对于单选下拉菜单可以通过selectedIndex属性轻松地访问到选项。

  Code:

  

复制代码 代码如下:

  <html>

  <head>

  <meta http-equiv="Content-Type" content="text/html; charset=utf-8" />

  <meta name="viewport" content="initial-scale=1.0, user-scalable=no" />

  <title>js操作表单</title>

  <script language="javascript">

  function checkSingle(){

  var oForm=document.forms["myForm1"];

  var oSelectBox=oForm.constellation;

  var iChoice=oSelectBox.selectedIndex;//获取选中项

  alert("您选中了:"+oSelectBox.options[iChoice].text);

  }

  </script>

  </head>

  <body>

  <form method="post" name="myForm1" action="">

  <p>

  <select id="constellation" name="constellation">

  <option value="Aries" selected="selected">白羊</option>

  <option value="Taurus">金牛</option>

  <option value="Gemin">双子</option>

  <option value="Leo">狮子</option>

  <option value="Virgo">处女</option>

  </select>

  </p>

  <p>

  <input type="button" value="查看选项" onClick="checkSingle();" />

  </p>

  </form>

  </body>

  </html>