ajax读取返回的json格式的数据

//alert(msg);//{"serverHost":"23","mail":"32","mailPassword":"23"}
//json = eval(json); 
//alert("===json:id=" + json.id + ",uname=" + json.uname + ",email=" + json.email); 
ajaxobj=eval("("+msg+")"); 
$("#serverHost").val(ajaxobj.serverHost);
$("#mail").val(ajaxobj.mail);
$("#mailPassword").val(ajaxobj.mailPassword);

$.ajax({ 
async : false,    
cache : false,    
type : ‘post‘,    
dataType : "json",    
url : "<%=path%>/process/process!getFileByTypeId.action?model.busiTypeId="+typeId+"&date="+new Date(),    
success : function(msg) {
if(msg){
for(var i=0;i<msg.length;i++){
$("#fileId").append("<option value=‘"+msg[i].id+"‘>"+msg[i].name+"</option>");
}
}
}    
});