<tr>
  <th>输入名称：</th>
  <td><input type='text' class='normal' name='name' pattern='required' alt='名称'id="checkText" onblur="checkName()" /><label>* 特价活动名称</label></td>
</tr>

function checkName()  
  {  
  //获取表单ID
   var cashName = document.getElementById("checkText").value; 
   //正则匹配 
   var result=cashName.match(/[`~!@#$%^&*()_+<>?:"{},.\/;'[\]]/im);  
   if(result!=null) {    
     document.getElementById("checkText").value="";
     alert ("名称不能含有非法字符！");
   }   
  }