Silverlight 与HTML元素交互操作

Silverlight  中的HtmlPage 和 HtmlElement 分别代表HTML页面和HTML元素

获取HTML元素改变他的属性

    <div>
        <img id="img1" src="Images/logo.jpg" />
    </div>

xaml.cs：

private void Button1_Click(object sender, RoutedEventArgs e)
        {
            //获取HTML中的img1对象
            HtmlElement img = HtmlPage.Document.GetElementById("img1");
            //根据输入值设置img1的html属性Width和Height
            img.SetAttribute("width", textBox1.Text);
            img.SetAttribute("height", textBox2.Text);
        }

HTML元素操作Silverlight

<div>        

        <select id="sel">
            <option value="Red">红ì色?</option>
            <option value="Green">绿ì色?</option>
            <option value="Blue">蓝?色?</option>
        </select>
    </div>

xaml.cs：

public htmldom2()
        {
            InitializeComponent();
            //获取select对象
            HtmlElement select = HtmlPage.Document.GetElementById("sel");
            //添加select的onchange事件
            select.AttachEvent("onchange"
                , new EventHandler<HtmlEventArgs>(select_onChange));
        }

        public void select_onChange(object sender, HtmlEventArgs e)
        {
            //获取select的选择值
            HtmlElement select = sender as HtmlElement;
            string value = select.GetAttribute("value");
            textBlock1.Text = value;
            //根据用户选择值来改变椭圆形的Fill值
            switch (value)
            {
                case "Red":
                    ellipse1.Fill = new SolidColorBrush(Colors.Red);
                    break;
                case "Green":
                    ellipse1.Fill = new SolidColorBrush(Colors.Green);
                    break;
                case "Blue":
                    ellipse1.Fill = new SolidColorBrush(Colors.Blue);
                    break;
            }
        }

HTML 文本 和 URL文本的编解码

Html编码

HttpUtility.HtmlEncode(textBlock1.Text);

HTML解码

HttpUtility.HtmlDecode(textBlock2.Text);

URL编码

HttpUtility.UrlEncode(textBlock3.Text);

URL解码

HttpUtility.UrlDecode(textBlock4.Text);

读写Cookie

//客户端Cookie读写类
public class CookieHelper
{
    //根据Key和Value写客户端Cookie
    public static void SetCookie(string key, string value)
    {
        DateTime expire = DateTime.UtcNow
            + TimeSpan.FromDays(30);
        string cookie = string.Format("{0}={1};expires={2}"
            , key, value, expire.ToString("R"));
        HtmlPage.Document.SetProperty("cookie"
            , cookie);
    }
    //根据Key读客户端Cookie
    public static string GetCookie(string key)
    {
        key += '=';
        //取出所有Cookie
        string[] cookies =
            HtmlPage.Document.Cookies.Split(';');
        //遍历Cookie值
        foreach (string cookie in cookies)
        {
            string cookieStr = cookie.Trim();
            //获取Cookie的key名称的位置
            if (cookieStr.StartsWith(key,
                StringComparison.OrdinalIgnoreCase))
            {
                //分隔出key的值
                string[] vals = cookieStr.Split('=');

                if (vals.Length >= 2)
                {
                    //返回值
                    return vals[1];
                }
                //如果没有找到则返回空白字符串
                return string.Empty;
            }
        }
        //如果没有Cookie则返回空白字符串
        return string.Empty;
    }
}

在Silverlight 中使用 Dom 的Window 对象

导航

         //根据输入值创建URI对象
         Uri uri = new Uri(tbUrl.Text, UriKind.RelativeOrAbsolute);
         //导航到URI地址
         HtmlPage.Window.Navigate(uri);

浏览器提示窗口

提示窗口

HtmlPage.Window.Alert("这是使用HtmlPage调用的消息框！");

判定窗口

if (HtmlPage.Window.Confirm("你确定吗？")){}

输入窗口

string password = HtmlPage.Window.Prompt("请输入密码");

示例出自Silverlight 3.0 开发详解与最佳实践一书