getFormData.js

//获取指定form中的所有的<input>对象    
function getElements(formId) {    
    var form = document.getElementById(formId);    
    var elements = new Array();    
    var tagElements = form.getElementsByTagName('input');    
    for (var j = 0; j < tagElements.length; j++){  
         elements.push(tagElements[j]);  
  
    }  
    return elements;    
}   
  
//获取单个input中的【name,value】数组  
function inputSelector(element) {    
  if (element.checked)    
     return [element.name, element.value];    
}    
      
function input(element) {    
    switch (element.type.toLowerCase()) {    
      case 'submit':    
      case 'hidden':    
      case 'password':    
      case 'text':    
        return [element.name, element.value];    
      case 'checkbox':    
      case 'radio':    
        return inputSelector(element);    
    }    
    return false;    
}    
  
//组合URL  
function serializeElement(element) {    
    var method = element.tagName.toLowerCase();    
    var parameter = input(element);    
    
    if (parameter) {    
      var key = encodeURIComponent(parameter[0]);    
      if (key.length == 0) return;    
    
      if (parameter[1].constructor != Array)    
        parameter[1] = [parameter[1]];    
          
      var values = parameter[1];    
      var results = [];    
      for (var i=0; i<values.length; i++) {    
        results.push(key + '=' + encodeURIComponent(values[i]));    
      }    
      return results.join('&');    
    }    
 }    
  
//调用方法     
function serializeForm(formId) {    
    var elements = getElements(formId);    
    var queryComponents = new Array();    
    
    for (var i = 0; i < elements.length; i++) {    
      var queryComponent = serializeElement(elements[i]);    
      if (queryComponent)    
        queryComponents.push(queryComponent);    
    }    
    
    return queryComponents.join('&');  
}    


// 使用

function getFormInfo(){  
    var params = serializeForm('login');  
    alert(params);  
}