//到页面底部下载源，配合效果跟好。 public class MvcApplication : System.Web.HttpApplication
{
protected void Application_Start()
{
RouteConfig.RegisterRoutes(RouteTable.Routes);
//调用RouteConfig类的RegisterRoutes方法注册路由
//RouteTable.Routes是一个储存Route的集合
}
}
我们转到RouteConfig类的定义
public class RouteConfig
{
public static void RegisterRoutes(RouteCollection routes)
{
routes.IgnoreRoute("{resource}.axd/{*pathInfo}");
//忽略可用的URL
// 例如： routes.IgnoreRoute("Home/Index");
//在浏览器输入 http://localhost:47662/Home/Index
//得到：HTTP 错误 404.0 - Not Found 的提示
//默认值
var defaults = new RouteValueDictionary { { "controller", "Home" }, { "action","Index" } };
//路由对象
Route R = new Route("{controller}/{action}/{*id}", null, null, null, new MvcRouteHandler());
//加入集合
RouteTable.Routes.Add("Default",R);
}
}
转到：Route 类去看怎么初始化构函数的
namespace MyRotue
{
//这个类不是系统的，是自己写的
public class Route : RouteBase
{
private ParsedRoute _parsedRoute;
private string _url;
public Route(string url, IRouteHandler routeHandler)
{
this.Url = url;
this.RouteHandler = routeHandler;
}
public Route(string url, RouteValueDictionary defaults, IRouteHandler routeHandler)
{
this.Url = url;
this.Defaults = defaults;
this.RouteHandler = routeHandler;
}
public Route(string url, RouteValueDictionary defaults, RouteValueDictionary constraints, IRouteHandler routeHandler)
{
this.Url = url;
this.Defaults = defaults;
this.Constraints = constraints;
this.RouteHandler = routeHandler;
}
public Route(string url, RouteValueDictionary defaults, RouteValueDictionary constraints, RouteValueDictionary dataTokens, IRouteHandler routeHandler)
{
this.Url = url; //URL模板
this.Defaults = defaults; //默认值
this.Constraints = constraints; //约束
this.DataTokens = dataTokens; //获取或设置传递到路由处理程序但未用于确定该路由是否匹配 URL 模式的自定义值。
this.RouteHandler = routeHandler; //路由处理请求的对象
//当初始化 this.Url 模板时：将给Url赋值
}
public string Url
{
get
{
return (this._url ?? string.Empty);
}
set
{
//this._parsedRoute:解析完的路由，把模板传入RouteParser(路由解析器)类的Parse()方法中，
//然后返回解析好了的路由。
this._parsedRoute = RouteParser.Parse(value);
this._url = value;
}
}// 这不是完全代码目前还用不到下面的方法，就先不贴出来了
}
我们转到RouteParser.Parse(Value)中出看下怎么解析的
using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
namespace MyRotue
{
public class RouteParser
{
public static ParsedRoute Parse(string routeUrl)
{
// -------------------------------
// 这是第一步，先进入这个方法
//判断routeUrl 是否为空
if (routeUrl == null)
{
routeUrl = string.Empty;
}
//判断是不是无效路由
if (IsInvalidRouteUrl(routeUrl))
{
throw new ArgumentException("出错了");
}
//拆分URL路径，如果routeUrl：Home/Index/Id
//将被拆分成:[Home],[/],[Index],[/],[Index] 这样的数组
IList<string> pathSegments = SplitUrlToPathSegmentStrings(routeUrl);
//验证URL部分
Exception exception = ValidateUrlParts(pathSegments);
if (exception != null)
{
throw exception;
}
//分类
return new ParsedRoute(SplitUrlToPathSegments(pathSegments));
}
//这不是全部代码}
我们转到IsInvalidRouteUrl(routeUrl)这个方法，看到是怎么判断的
internal static bool IsInvalidRouteUrl(string routeUrl)
{
//检查开头字符串,是否有 "~" 和 "/"
if (!routeUrl.StartsWith("~", StringComparison.Ordinal) && !routeUrl.StartsWith("/", StringComparison.Ordinal))
{
//在判断字符串有没有 "?"
return (routeUrl.IndexOf(‘?‘) != -1);
}
return true;
}
转到：SplitUrlToPathSegmentStrings（）这个方法
internal static IList<string> SplitUrlToPathSegmentStrings(string url)
{
List<string> list = new List<string>();
if (!string.IsNullOrEmpty(url))
{
int index;
for (int i = 0; i < url.Length; i = index + 1)
{
//获取"/" 在 url中的位置
index = url.IndexOf(‘/‘, i);
if (index == -1)
{
// 获取最后一个参数
string str = url.Substring(i);
if (str.Length > 0)
{
list.Add(str);
}
return list;
}
//获取参数
string item = url.Substring(i, index - i);
if (item.Length > 0)
{
list.Add(item);
}
list.Add("/");
}
}
return list;
}
转到 ValidateUrlParts()方法
private static Exception ValidateUrlParts(IList<string> pathSegments)
{
//使用参数名称
HashSet<string> usedParameterNames = new HashSet<string>(StringComparer.OrdinalIgnoreCase);
bool? nullable = null;
foreach (string str in pathSegments)
{
bool flag2;
if (!nullable.HasValue)
{
//判断是不是分割符
nullable = new bool?(IsSeparator(str));
flag2 = nullable.Value;
}
else
{
flag2 = IsSeparator(str);
//如果连续有两个"/"就执行异常
if (flag2 && nullable.Value)
{
return new ArgumentException("出错了");
}
nullable = new bool?(flag2);
}
if (!flag2)
{
Exception exception;
//解析URL分类
IList<PathSubsegment> pathSubsegments = ParseUrlSegment(str, out exception);
if (exception != null)
{
return exception;
}
//验证URL分类
exception = ValidateUrlSegment(pathSubsegments, usedParameterNames, str);
if (exception != null)
{
return exception;
}
}
}
return null;
}转到：IsSeparator
internal static bool IsSeparator(string s)
{
return string.Equals(s, "/", StringComparison.Ordinal);
}
转到：ParseUrlSegment（）
private static IList<PathSubsegment> ParseUrlSegment(string segment, out Exception exception)
{
int startIndex = 0;
List<PathSubsegment> list = new List<PathSubsegment>();
// 判断是不是区域
int num2 = IndexOfFirstOpenParameter(segment, startIndex);
if (num2 == -1)
{
//得到字符串
string str = GetLiteral(segment.Substring(startIndex));
if (str == null)
{
exception = new ArgumentException("出错了");
return null;
}
if (str.Length > 0)
{
list.Add(new LiteralSubsegment(str));
exception = null;
return list;
}
}
//检查字符串，是否有“}”，没有就报错
if (num2 >=1)
{
exception = new ArgumentException("出错了");
return null;
}
int index = segment.IndexOf(‘}‘, num2 + 1);
if (index != segment.Length - 1)
{
exception = new ArgumentException("出错了");
return null;
}
//获取参数名字
string parameterName = segment.Substring(num2 + 1, (index - num2) - 1);
list.Add(new ParameterSubsegment(parameterName));
exception = null;
return list;
}
转到：IndexOfFirstOpenParameter
private static int IndexOfFirstOpenParameter(string segment, int startIndex)
{
startIndex = segment.IndexOf(‘{‘, startIndex);
return startIndex;
}
转到：GetLiteral
private static string GetLiteral(string segmentLiteral)
{
string str = segmentLiteral.Replace("{{", "").Replace("}}", "");
if (!str.Contains("{") && !str.Contains("}"))
{
return segmentLiteral.Replace("{{", "{").Replace("}}", "}");
}
return null;
}
List<PathSubsegment> list = new List<PathSubsegment>();
我们来看看PathSubsegment类吧，
internal abstract class PathSubsegment
{
protected PathSubsegment() { }
}
//文字路劲部分，存放区域的，如：JB/{Home}/{Index}/{Id},他存放的就是JB
internal sealed class LiteralSubsegment : PathSubsegment
{
// Methods
public LiteralSubsegment(string literal)
{
this.Literal = literal;
}
// Properties
public string Literal
{
get;
set;
}
}
}
//参数子段，存放参数的
internal sealed class ParameterSubsegment : PathSubsegment
{
// Methods
public ParameterSubsegment(string parameterName)
{
if (parameterName.StartsWith("*", StringComparison.Ordinal))
{
this.ParameterName = parameterName.Substring(1);
this.IsCatchAll = true;
}
else
{
this.ParameterName = parameterName;
}
}
// Properties
public bool IsCatchAll { get; private set; }
public string ParameterName {get; private set; }
}
//存放 "/"符号的
internal sealed class SeparatorPathSegment : PathSegment
{
// Methods
public SeparatorPathSegment() { }
}
这两个都是他的子类
转到： ValidateUrlSegment
private static Exception ValidateUrlSegment(IList<PathSubsegment> pathSubsegments, HashSet<string> usedParameterNames, string pathSegment)
{
Type type = null;
foreach (PathSubsegment subsegment in pathSubsegments)
{
if ((type != null) && (type == subsegment.GetType()))
{
return new ArgumentException("出错了");
}
type = subsegment.GetType();
if (!(subsegment is LiteralSubsegment))
{
ParameterSubsegment subsegment3 = subsegment as ParameterSubsegment;
if (subsegment3 != null)
{
string parameterName = subsegment3.ParameterName;
//判断里面有没有"/"
if (!IsValidParameterName(parameterName))
{
return new ArgumentException("出错了");
}
//判断有没有重复
if (usedParameterNames.Contains(parameterName))
{
return new ArgumentException("出错了");
}
usedParameterNames.Add(parameterName);
}
}
}
return null;
}
现在转到： return new ParsedRoute(SplitUrlToPathSegments(pathSegments));
using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.Web.Routing;
namespace MyRotue
{
public class ParsedRoute
{
public ParsedRoute(IList<PathSegment> pathSegments)
{
this.PathSegments = pathSegments;
}
public RouteValueDictionary Match(string virtualPath, RouteValueDictionary defaultValues)
{
//拆分URL
IList<string> source = RouteParser.SplitUrlToPathSegmentStrings(virtualPath);
if (defaultValues == null)
{
defaultValues = new RouteValueDictionary();
}
//匹配值
RouteValueDictionary matchedValues = new RouteValueDictionary();
bool flag = false;
bool flag2 = false;
for (int i = 0; i < this.PathSegments.Count; i++)
{
PathSegment segment = this.PathSegments[i];
if (source.Count <= i)
{
flag = true;
}
string a = flag ? null : source[i];
if (segment is SeparatorPathSegment)
{
if (!flag && !string.Equals(a, "/", StringComparison.Ordinal))
{
return null;
}
}
else
{
ContentPathSegment contentPathSegment = segment as ContentPathSegment;
if (contentPathSegment != null)
{
if (contentPathSegment.IsCatchAll)
{
this.MatchCatchAll(contentPathSegment, source.Skip<string>(i), defaultValues, matchedValues);
flag2 = true;
}
else if (!this.MatchContentPathSegment(contentPathSegment, a, defaultValues, matchedValues))
{
return null;
}
}
}
}
if (!flag2 && (this.PathSegments.Count < source.Count))
{
for (int j = this.PathSegments.Count; j < source.Count; j++)
{
if (!RouteParser.IsSeparator(source[j]))
{
return null;
}
}
}
if (defaultValues != null)
{
foreach (KeyValuePair<string, object> pair in defaultValues)
{
if (!matchedValues.ContainsKey(pair.Key))
{
matchedValues.Add(pair.Key, pair.Value);
}
}
}
return matchedValues;
}
private void MatchCatchAll(ContentPathSegment contentPathSegment, IEnumerable<string> remainingRequestSegments, RouteValueDictionary defaultValues, RouteValueDictionary matchedValues)
{
object obj2;
string str = string.Join(string.Empty, remainingRequestSegments.ToArray<string>());
ParameterSubsegment subsegment = contentPathSegment.Subsegments[0] as ParameterSubsegment;
if (str.Length > 0)
{
obj2 = str;
}
else
{
defaultValues.TryGetValue(subsegment.ParameterName, out obj2);
}
matchedValues.Add(subsegment.ParameterName, obj2);
}
private bool MatchContentPathSegment(ContentPathSegment routeSegment, string requestPathSegment, RouteValueDictionary defaultValues, RouteValueDictionary matchedValues)
{
if (string.IsNullOrEmpty(requestPathSegment))
{
if (routeSegment.Subsegments.Count <= 1)
{
object obj2;
ParameterSubsegment subsegment = routeSegment.Subsegments[0] as ParameterSubsegment;
if (subsegment == null)
{
return false;
}
if (defaultValues.TryGetValue(subsegment.ParameterName, out obj2))
{
matchedValues.Add(subsegment.ParameterName, obj2);
return true;
}
}
return false;
}
int length = requestPathSegment.Length;
int num2 = routeSegment.Subsegments.Count - 1;
ParameterSubsegment subsegment2 = null;
LiteralSubsegment subsegment3 = null;
while (num2 >= 0)
{
int num3 = length;
ParameterSubsegment subsegment4 = routeSegment.Subsegments[num2] as ParameterSubsegment;
if (subsegment4 != null)
{
subsegment2 = subsegment4;
}
else
{
LiteralSubsegment subsegment5 = routeSegment.Subsegments[num2] as LiteralSubsegment;
if (subsegment5 != null)
{
subsegment3 = subsegment5;
int startIndex = length - 1;
if (subsegment2 != null)
{
startIndex--;
}
if (startIndex < 0)
{
return false;
}
int num5 = requestPathSegment.LastIndexOf(subsegment5.Literal, startIndex, StringComparison.OrdinalIgnoreCase);
if (num5 == -1)
{
return false;
}
if ((num2 == (routeSegment.Subsegments.Count - 1)) && ((num5 + subsegment5.Literal.Length) != requestPathSegment.Length))
{
return false;
}
num3 = num5;
}
}
if ((subsegment2 != null) && (((subsegment3 != null) && (subsegment4 == null)) || (num2 == 0)))
{
int num6;
int num7;
if (subsegment3 == null)
{
if (num2 == 0)
{
num6 = 0;
}
else
{
num6 = num3;
}
num7 = length;
}
else if ((num2 == 0) && (subsegment4 != null))
{
num6 = 0;
num7 = length;
}
else
{
num6 = num3 + subsegment3.Literal.Length;
num7 = length - num6;
}
string str = requestPathSegment.Substring(num6, num7);
if (string.IsNullOrEmpty(str))
{
return false;
}
matchedValues.Add(subsegment2.ParameterName, str);
subsegment2 = null;
subsegment3 = null;
}
length = num3;
num2--;
}
return true;
}
private IList<PathSegment> PathSegments { get; set; }
}
}
好了，差不多了，你看到这里，然后再下载源码，调试一遍，就因该了路由匹配流程了。
源码中肯定，有很多错误，请指教。 源码：http://files.cnblogs.com/liek/MyRotue.rar
源码中肯定，有很多错误，请指教。
源码：MVC 路由源码解析
时间： 2024-10-30 13:49:29