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WindowsPhone中XML和Json格式的数据解析

        由于WindowsPhone的沙箱机制,致使关系型数据库无法很好的在WindowsPhone手机中大行其道,此外,大型的数据库一方面打破了WindowsPhone的沙箱机制,破坏了系统的严密、安全性,可能会带来一些意想不到的危害,另一方面数据库服务的开启会一直占用系统的内存。但有时候有些应用却又需要存储大量的数据,这个时候XML的优势就体现的淋漓尽致了,此外一些WebService返回的结果大都也是XML格式或者Json格式的数据,这时候就要用到XML或者Json解析返回的数据,这便是本文的初衷。

先来讲一下XML解析本地的数据,

一、首先应在当前项目下创建一个.xml文件,例如本例的SpokenEnglish.xml文件

文件的格式如下:

<?xml version="1.0" encoding="utf-8" ?>

<SpokenEnglish>

  <Items>

    <Item>

      <Spoken>1. I see.</Spoken>

      <Chinese>我明白了。</Chinese>

    </Item>

    <Item>

      <Spoken>2. I quit!</Spoken>

      <Chinese>我不干了! </Chinese>

    </Item>

    <Item>

      <Spoken>3. Let go! </Spoken>

      <Chinese>放手! </Chinese>

    </Item>

    <Item>

      <Spoken>4. Me too.</Spoken>

      <Chinese>我也是。</Chinese>

    </Item>

    <Item>

      <Spoken>5. My god!</Spoken>

      <Chinese>天哪!</Chinese>

    </Item>

</Items>

</SpokenEnglish>

这是本地的数据存储文件

下边再建一个与源数据相映射的类:SpokenEnglishes.cs

如下:

在使用之前应先加入以下命名空间

using System.Collections.Generic;//对应List<T>泛型集合

using System.Linq;//对应Element.load().Select();

using System.Xml.Linq;//对应XDocument

namespace XMLAndJSON       

{

    public class SpokenEnglishes

    {

        public static readonly string xmlPath;//数据文件的路径

        public string Spoken

        {

            get;

            set;

        }

        public string Chinese

        {

            get;

            set;

        }

       static SpokenEnglishes()

        {

            xmlPath = @"SpokenEnglish.xml";

        }

XML解析方法一

        public static List<SpokenEnglishes> GetAllSpokenEnglishes()//获取数据文件中的数据,并映射为SpokenEnglishes类

        {

           return XElement.Load(xmlPath).Element("Items").Descendants("Item").Select(item => new SpokenEnglishes()

            {

                Spoken = item.Element("Spoken").Value,

                Chinese=item.Element("Chinese").Value

            }).ToList();

        }

XML解析方法二

        public static List<SpokenEnglishes> GetAll()//与上一个函数功能相同,只不过是另一个XML解析方法

        {

            XDocument xDocument = XDocument.Load("SpokenEnglish.xml");

            return xDocument.Descendants("Item").Select(item => new SpokenEnglishes()

            {

                Chinese = item.Element("Chinese").Value,

                Spoken = item.Element("Spoken").Value

            }).ToList();

        }

    }

}

然后就是在MainPage.xaml页进行UI的布局和数据的绑定

主要代码如下:

<Grid x:Name="ContentPanel" Grid.Row="1" Margin="12,0,12,0">

            <ListBox Height="591" HorizontalAlignment="Left" Margin="10,10,0,0" Name="listBox1" VerticalAlignment="Top"

                    Width="440" >      

                <ListBox.ItemTemplate>

                    <DataTemplate>

                        <StackPanel Orientation="Vertical">

                        <TextBlock Name="spoken" Text="{Binding Spoken}"/>//与SpokenEnglish类属性相绑定

                        <TextBlock Text="{Binding Chinese}"/>

                        </StackPanel>

                    </DataTemplate>

                </ListBox.ItemTemplate>

            </ListBox>

        </Grid>

然后在MainPage.xaml.cs页的构造函数里为listbox1指定数据源

代码如下:  listBox1.ItemsSource = SpokenEnglishes.GetAll();//静态类SpokenEnglishes调用其GetAll()方法获取List<SpokenEnglishes>的集合

运行效果如下:

二、用XML解析Web服务返回的数据跟解析本地数据的方法差不多,

大体步骤如下:

1、先根据返回的XML数据格式创建与数据相互映射的实体类:

例如:AirLine类,航班信息类

public class AirLine1

    {

        public string Company1 { get; set; }

        public string AirLineCode1 { get; set; }

        public string StartDrome1 { get; set; }

        public string EndDrome1 { get; set; }

        public string StartTime1 { get; set; }

        public string EndTime1 { get; set; }

        public string AirLineStop1 { get; set; }

        public string Week1 { get; set; }

    }

然后在异步返回函数中做出如下的解析:

  void airws_getDomesticAirlinesTimeCompleted(object sender, AirLineWS.getDomesticAirlinesTimeCompletedEventArgs e)

        {

            try

            {//关键的解析部分

                List<AirLine1> airlinelist = e.Result.Nodes.Descendants("AirlinesTime").Select(

                    item => new AirLine1()

                    {

                        Company1 = item.Element("Company").Value,

                        AirLineCode1 = item.Element("AirlineCode").Value,

                        StartDrome1 = item.Element("StartDrome").Value,

                        EndDrome1 = item.Element("ArriveDrome").Value,

                        StartTime1 = item.Element("StartTime").Value,

                        EndTime1 = item.Element("ArriveTime").Value,

                        AirLineStop1 = item.Element("AirlineStop").Value,

                        Week1 = item.Element("Week").Value

                    }).ToList();

                foreach (AirLine1 al in airlinelist)

                {

                    TextBlock t = new TextBlock();

                    t.Text = "航空公司:" + al.Company1;

                    t.FontSize = 24;

                    TextBlock t1 = new TextBlock();

                    t1.Text = "航班号:" + al.AirLineCode1;

                    t1.FontSize = 24;

                    TextBlock t2 = new TextBlock();

                    t2.Text = "出发机场:" + al.StartDrome1;

                    t2.FontSize = 24;

                    TextBlock t3 = new TextBlock();

                    t3.Text = "到达机场:" + al.EndDrome1;

                    t3.FontSize = 24;

                    TextBlock t4 = new TextBlock();

                    t4.Text = "出发时间:" + al.StartTime1;

                    t4.FontSize = 24;

                    TextBlock t5 = new TextBlock();

                    t5.Text = "到达时间:" + al.EndTime1;

                    t5.FontSize = 24;

                    TextBlock t6 = new TextBlock();

                    t6.Text = "经停:" + al.AirLineStop1 + "次";

                    t6.FontSize = 24;

                    TextBlock t7 = new TextBlock();

                    t7.Text = "飞行周期:" + al.Week1;

                    t7.FontSize = 24;

                    StackPanel sp = new StackPanel();

                    sp.Margin = new Thickness(0, 10, 0, 0);

                    sp.Width = 400;

                    sp.Children.Add(t);

                    sp.Children.Add(t1);

                    sp.Children.Add(t2);

                    sp.Children.Add(t3);

                    sp.Children.Add(t4);

                    sp.Children.Add(t5);

                    sp.Children.Add(t6);

                    sp.Children.Add(t7);

                    stackPanel1.Children.Add(sp);

                }

            }

            catch (Exception ee)

            {

                MessageBox.Show("很抱歉,找不到您所要查询的信息,请稍后再试");

            }

        }

这个例子是一个航班查询的实力,在使用之前需要先添加WebService 服务,这里主要是讲XML存储本地数据和解析,因此对于web应用方便就不多讲了,如果有需要源码的朋友可以给我留个邮箱,到时发到你们邮箱。

运行的效果图:

三、数据的序列化和反序列化

1、序列化:

     事先写好一个类例如:

People类

public class People

{

   string Name{get;set;}

   string Address{get;set;}

}

static void Main(string[] args)

        {

            var people = new People()

            {

                Name = “Olive",

                Address="北京"

            };

序列化:

            //序列化将序列化People类的实例写入内存流中,需要引入using System.Runtime.Serialization;命名空间

            var serializer = new DataContractJsonSerializer(typeof(People));

            var stream = new MemoryStream();

            serializer.WriteObject(stream, people);

            //从内存流中中读到string中,即生成Json

            byte[] dataBytes = new byte[stream.Length];

            stream.Position = 0;

            stream.Read(dataBytes, 0,(int) stream.Length);

            string dataString = Encoding.UTF8.GetString(dataBytes);

            Console.WriteLine(dataString);//即:序列化之后的Json格式的字符串

            Console.ReadLine();

反序列化:

           //反序列化先将json格式的字符串读入到内存中,然后在经过反序列化成类的对象

            var mStream = new MemoryStream(Encoding.UTF8.GetBytes(dataString));

            DataContractJsonSerializer dcJoson = new DataContractJsonSerializer(typeof(People));

            People pp=(People) dcJoson.ReadObject(mStream);

            Console.WriteLine(pp.Name);//输入People类对象的Name属性

            Console.ReadLine();

        }

序列化和反序列化主要用到了using System.Runtime.Serialization;命名空间下的 DataContractJsonSerializer类的两个实例方法

WirteObject()和ReadObject()

在WindowsPhone中解析Json需要同时加入using System.Runtime.Serialization;命名空间和System.Servicemodel.Web命名空间

其解析方法和桌面程序解析差不多,

主要是在异步回调函数中将返回的字符串进行解析,先创建和返回数据相映射的类,然后在用DataContractJsonSerilzer类的实例方法

ReadObject()将返回数据反序列化为类的实例。