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  • 对用户控件的访问方式重写

    因为项目里面需要记录一下重写的方法以备后用

    首先增加一个继承IHttpHandler的截获类

    代码
    public class UserControlRenderingHandler : IHttpHandler
    {
    public void ProcessRequest(HttpContext context)
    {
    string fileType = context.Request.FilePath;
    string appRelativePath = context.Request.AppRelativeCurrentExecutionFilePath;
    string controlPath = appRelativePath.ToLower().Replace(".uc", ".ascx");

    ViewManager
    <UserControl> viewManager = new ViewManager<UserControl>();
    UserControl control
    = viewManager.LoadViewControl(controlPath);

    SetPropertyValues(control, context);

    context.Response.ContentType
    = "text/html";
    context.Response.Write(viewManager.RenderView(control));
    }

    private static Dictionary<
    Type,
    Dictionary
    <
    PropertyInfo,
    List
    <UserControlRenderingPropertyAttribute>>> s_metadataCache =
    new Dictionary<
    Type,
    Dictionary
    <
    PropertyInfo,
    List
    <UserControlRenderingPropertyAttribute>>>();
    private static Dictionary<PropertyInfo, object> s_defaultValueCache =
    new Dictionary<PropertyInfo, object>();
    private static object s_mutex = new object();

    private static Dictionary<
    PropertyInfo,
    List
    <UserControlRenderingPropertyAttribute>> GetMetadata(Type type)
    {
    if (!s_metadataCache.ContainsKey(type))
    {
    lock (s_mutex)
    {
    if (!s_metadataCache.ContainsKey(type))
    {
    s_metadataCache[type]
    = LoadMetadata(type);
    }
    }
    }

    return s_metadataCache[type];
    }

    private static Dictionary<
    PropertyInfo,
    List
    <UserControlRenderingPropertyAttribute>> LoadMetadata(Type type)
    {
    Dictionary
    <PropertyInfo, List<UserControlRenderingPropertyAttribute>> result = new Dictionary<PropertyInfo, List<UserControlRenderingPropertyAttribute>>();
    PropertyInfo[] properties
    = type.GetProperties(BindingFlags.Public | BindingFlags.Instance | BindingFlags.SetProperty);
    foreach (PropertyInfo p in properties)
    {
    object[] oo = p.GetCustomAttributes(typeof(UserControlRenderingPropertyAttribute), true);
    if (oo.Length > 0)
    {
    List
    <UserControlRenderingPropertyAttribute> list = new List<UserControlRenderingPropertyAttribute>();
    list.Add(((UserControlRenderingPropertyAttribute)oo[
    0]));
    result[p]
    = list;
    }
    }
    return result;
    }

    private static object GetDefaultValue(PropertyInfo property)
    {
    if (!s_defaultValueCache.ContainsKey(property))
    {
    lock (s_mutex)
    {
    if (!s_defaultValueCache.ContainsKey(property))
    {
    object[] attributes = property.GetCustomAttributes(typeof(DefaultValueAttribute), true);
    object value = attributes.Length > 0 ?
    ((DefaultValueAttribute)attributes[
    0]).Value : null;
    s_defaultValueCache[property]
    = value;
    }
    }
    }

    return s_defaultValueCache[property];
    }

    public static void SetPropertyValues(UserControl control, HttpContext context)
    {
    Dictionary
    <
    PropertyInfo,
    List
    <UserControlRenderingPropertyAttribute>> metadata = GetMetadata(control.GetType());
    foreach (PropertyInfo property in metadata.Keys)
    {
    object value = GetValue(metadata[property], context) ?? GetDefaultValue(property);
    if (value != null)
    {
    property.SetValue(control, Convert.ChangeType(value, property.PropertyType),
    null);
    }
    }
    }

    private static object GetValue(
    IEnumerable
    <UserControlRenderingPropertyAttribute> metadata,
    HttpContext context)
    {
    foreach (UserControlRenderingPropertyAttribute att in metadata)
    {
    NameValueCollection collection
    = (att.Source == UserControlRenderingPropertySource.QueryString) ?
    context.Request.QueryString : context.Request.Form;
    object value = collection[att.Key];

    if (value != null) return value;
    }

    return null;
    }

    public bool IsReusable
    {
    get
    {
    return false;
    }
    }

    上面类相关的东西

    代码
    public class ViewManager<T> where T : UserControl
    {
    private AjaxPageBase m_pageHolder;

    public T LoadViewControl(string path)
    {
    this.m_pageHolder = new AjaxPageBase();

    return (T)this.m_pageHolder.LoadControl(path);
    }

    public string RenderView(T control)
    {
    StringWriter output
    = new StringWriter();
    this.m_pageHolder.Controls.Add(control);
    HttpContext.Current.Server.Execute(
    this.m_pageHolder, output, true);
    return output.ToString();
    }
    }
    代码
    public class AjaxPageBase : Page
    {
    public override void VerifyRenderingInServerForm(Control control)
    {

    }

    protected override void OnError(EventArgs e)
    {



    }
    }

    下面这个是对form表单的参数截获

    代码
    public enum UserControlRenderingPropertySource
    {
    Form,
    QueryString
    }

    [AttributeUsage(AttributeTargets.Property, AllowMultiple
    = true, Inherited = true)]
    public class UserControlRenderingPropertyAttribute : Attribute
    {
    string _key;

    public string Key
    {
    get { return _key; }
    set { _key = value; }
    }

    UserControlRenderingPropertySource _source;

    public UserControlRenderingPropertySource Source
    {
    get { return _source; }
    set { _source = value; }
    }
    }

    这样就将用户的控件.ascx转成.uc的方式 重新写出来了。

    解决了.ascx不能直接访问的问题。

    web.config的<httpHandlers>节增加

    <add verb="*" path="*.uc" type="Core.Web.UserControlRenderingHandler"/>

    再到IIS6中增加映射

    IIS7配置

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  • 原文地址:https://www.cnblogs.com/hack1506/p/1921692.html
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