简单了解Ajax表单序列化的实现方法

function serialize(form){
var parts=[],
field=null,
i,
len,
j,
optLen,
option,
optValue;
for (i = 0; i < form.elements.length; i++) {
field=form.elements[i];
switch (field.type) {
case 'select-one':
case 'select-multiple':
if(field.name.length){
for (var j = 0; j < field.options.length; j++) {
option=field.options[j];
if (option.selected) {
optValue="";
if (option.hasAttribute) {
optValue=(option.hasAttribute('value') ? option.value : option.text);
}else{
optValue=(option.attribute['value'].specified ? option.value : option.text);
}
parts.push(encodeURIComponent(field.name) + "=" + encodeURIComponent(optValue));
}
}
}
break;
case undefined: //字段集
case "file": //文本输入
case "submit": //提交按钮
case "reset": //重置按钮
case "button": //自定义按钮
break;
case "radio": //单选按钮
case "checkbox": //复选框
if (!field.checked) {
break;
}
//执行默认操作
default:
//不包含没有名字的表单字段
if(field.name.length){
parts.push(encodeURIComponent(field.name) + "=" + encodeURIComponent(field.value));
}
}
}
return parts.join("&");
}