上一节我们讲了如何捕获异常和记录日志，这一节我们讲，没有捕获的或者忘记捕获的异常包括404错误等，我们统一处理这个异常。
这一讲是利用 Application_Error 捕获所有异常，全局的异常处理为了减少代码，统一异常处理，Application_Error位于Global.asax里面，
protected void Application_Error(object sender, EventArgs e)
当一个异常在调用堆栈中没有被处理，也没有被框架代码处理时，我们说这个异常未处理，它将被ASP.NET捕获
它将捕获所有 Application 级别的 UnhandleException 和 HttpException（比如：访问的页面不存在等）
总之，在这里处理的话，那么在页面中的所有 try/catch 处理都可以不要了,但是我们为了记录日志，在BLL层还是要try catch
对此未处理错误的处理方法是显示一个页面，列出该未处理异常的详细情况。
我们通过 Application_Error事件把错误写进对应的文件里面或者数据库中。
/// <summary>
/// 全局的异常处理
/// </summary>
/// <param name="sender"></param>
/// <param name="e"></param>
protected void Application_Error(object sender, EventArgs e)
{
string s = HttpContext.Current.Request.Url.ToString();
HttpServerUtility server = HttpContext.Current.Server;
if (server.GetLastError() != null)
{
Exception lastError = server.GetLastError();
// 此处进行异常记录，可以记录到数据库或文本，也可以使用其他日志记录组件。
ExceptionHander.WriteException(lastError);
Application["LastError"] = lastError;
int statusCode = HttpContext.Current.Response.StatusCode;
string exceptionOperator = "/SysException/Error";
try
{
if (!String.IsNullOrEmpty(exceptionOperator))
{
exceptionOperator = new System.Web.UI.Control().ResolveUrl(exceptionOperator);
string url = string.Format("{0}?ErrorUrl={1}", exceptionOperator, server.UrlEncode(s));
string script = String.Format("<script language='javascript' type='text/javascript'>window.top.location='{0}';</script>", url);
Response.Write(script);
Response.End();
}
}
catch { }
}
}嘿嘿，我创造了一个错误 Convert.ToInt16("dddd");下面是错误的显示页面
关于错误页面的制作在控制器SysExceptionController增加
public ActionResult Error() {BaseException ex = new BaseException(); return View(ex); }</code></pre></div></div><p>添加BaseException类</p><div class="rno-markdown-code"><div class="rno-markdown-code-toolbar"><div class="rno-markdown-code-toolbar-info"><div class="rno-markdown-code-toolbar-item is-type"><span class="is-m-hidden">代码语言：</span>javascript</div></div><div class="rno-markdown-code-toolbar-opt"><div class="rno-markdown-code-toolbar-copy"><i class="icon-copy"></i><span class="is-m-hidden">复制</span></div></div></div><div class="developer-code-block"><pre class="prism-token token line-numbers language-javascript"><code class="language-javascript" style="margin-left:0"> public class BaseException { #region 变量 private string exceptionMessage; private string exceptionName; private string innerExceptionMessage; private string innerExceptionName; private bool isShow; private Exception outermostException; private string sourceErrorFile; private string sourceErrorRowID; private string stackInfo; private string targetSite; #endregion #region 属性 public string ErrorPageUrl { get { return this.GetExceptionUrl(); } } public Exception Exception { get { return (HttpContext.Current.Session["Exception"] as Exception); } private set { HttpContext.Current.Session["Exception"] = value; } } public string ExceptionMessage { get { return this.exceptionMessage; } private set { this.exceptionMessage = value; } } public string ExceptionName { get { return this.exceptionName; } private set { this.exceptionName = value; } } public string InnerExceptionMessage { get { return this.innerExceptionMessage; } private set { this.innerExceptionMessage = value; } } public string InnerExceptionName { get { return this.innerExceptionName; } private set { this.innerExceptionName = value; } } public bool IsShowStackInfo { get { return this.isShow; } private set { this.isShow = value; } } public string SourceErrorFile { get { return this.sourceErrorFile; } private set { this.sourceErrorFile = value; } } public string SourceErrorRowID { get { return this.sourceErrorRowID; } private set { this.sourceErrorRowID = value; } } public string StackInfo { get { return this.stackInfo; } private set { this.stackInfo = value; } } public string TargetSite { get { return this.targetSite; } private set { this.targetSite = value; } } #endregion public BaseException() { this.outermostException = null; this.exceptionName = null; this.exceptionMessage = null; this.innerExceptionName = null; this.innerExceptionMessage = null; this.targetSite = null; this.stackInfo = null; this.sourceErrorFile = null; this.sourceErrorRowID = null; this.isShow = false; try { this.Exception = HttpContext.Current.Application["LastError"] as Exception; if (this.Exception != null) { this.outermostException = this.Exception; if ((this.Exception is HttpUnhandledException) && (this.Exception.InnerException != null)) { this.Exception = this.Exception.InnerException; } this.ExceptionName = this.GetExceptionName(this.Exception); this.ExceptionMessage = this.GetExceptionMessage(this.Exception); if (this.Exception.InnerException != null) { this.InnerExceptionName = this.GetExceptionName(this.Exception.InnerException); this.InnerExceptionMessage = this.GetExceptionMessage(this.Exception.InnerException); } this.TargetSite = this.GetTargetSite(this.Exception); this.StackInfo = this.GetStackInfo(this.Exception); if ((this.outermostException is HttpUnhandledException) && (this.outermostException.InnerException != null)) { this.StackInfo = this.StackInfo + "\r\n<a href='#' onclick=\"if(document.getElementById('phidden').style.display=='none') document.getElementById('phidden').style.display='block'; else document.getElementById('phidden').style.display='none'; return false;\"><b>[" + this.outermostException.GetType().ToString() + "]</b></a>\r\n"; this.StackInfo = this.StackInfo + "<pre id='phidden' style='display:none;'>" + this.outermostException.StackTrace + "</pre>"; } this.SourceErrorFile = this.GetSourceErrorFile(); this.SourceErrorRowID = this.GetSourceErrorRowID(); this.IsShowStackInfo = true; } HttpContext.Current.Session["LastError"] = null; } catch (Exception exception) { this.ExceptionMessage = "异常基页出错" + exception.Message; } } #region 方法 private string GetExceptionMessage(Exception ex) { return ex.Message; } private string GetExceptionMessageForLog() { StringBuilder builder = new StringBuilder(50); builder.AppendFormat("<ExceptionName>{0}</ExceptionName>", this.ExceptionName); builder.AppendFormat("<ExceptionMessage>{0}</ExceptionMessage>", this.ExceptionMessage); builder.AppendFormat("<InnerExceptionName>{0}</InnerExceptionName>", this.InnerExceptionName); builder.AppendFormat("<InnerExceptionMessage>{0}</InnerExceptionMessage>", this.InnerExceptionMessage); builder.AppendFormat("<TargetSite>{0}</TargetSite>", this.TargetSite); builder.AppendFormat("<ErrorPageUrl>{0}</ErrorPageUrl>", this.ErrorPageUrl); builder.AppendFormat("<SourceErrorFile>{0}</SourceErrorFile>", this.SourceErrorFile); builder.AppendFormat("<SourceErrorRowID>{0}</SourceErrorRowID>", this.SourceErrorRowID); return builder.ToString(); } private string GetExceptionMessageForMail() { StringBuilder builder = new StringBuilder(50); builder.Append("<ExceptionInfo>"); builder.Append(this.GetExceptionMessageForLog()); builder.AppendFormat("<StackInfo><![CDATA[{0}]]></StackInfo>", this.StackInfo); builder.Append("</ExceptionInfo>"); return builder.ToString(); } private string GetExceptionName(Exception ex) { string str = null; if (ex != null) { str = ex.GetType().FullName; } return str; } private string GetExceptionUrl() { string str = null; if (HttpContext.Current.Request["ErrorUrl"] != null) { str = HttpContext.Current.Request["ErrorUrl"].ToString(); } return str; } private string GetSourceErrorFile() { string stackInfo = this.StackInfo; string[] strArray = new string[0]; if (stackInfo == null) { return stackInfo; } strArray = stackInfo.Split(new string[] { "位置", "行号" }, StringSplitOptions.RemoveEmptyEntries); if (strArray.Length >= 3) { stackInfo = strArray[1]; if (stackInfo.LastIndexOf(":") == (stackInfo.Length - 1)) { stackInfo = stackInfo.Substring(0, stackInfo.Length - 1); } return stackInfo; } return ""; } private string GetSourceErrorRowID() { string stackInfo = this.StackInfo; string[] strArray = new string[0]; if (stackInfo == null) { return stackInfo; } strArray = stackInfo.Split(new string[] { "行号" }, StringSplitOptions.RemoveEmptyEntries); if (strArray.Length >= 2) { stackInfo = strArray[1].Trim(); string[] strArray2 = stackInfo.Split(new string[] { "\r\n" }, StringSplitOptions.RemoveEmptyEntries); if (strArray2.Length >= 2) { stackInfo = strArray2[0]; } return stackInfo; } return ""; } private string GetStackInfo(Exception ex) { string str = null; if (ex != null) { str = "<b>[" + ex.GetType().ToString() + "]</b>\r\n" + ex.StackTrace; if (ex.InnerException != null) { str = this.GetStackInfo(ex.InnerException) + "\r\n" + str; } } return str; } private string GetTargetSite(Exception ex) { string str = null; if (ex != null) { ex = this.GetBenmostException(ex); MethodBase targetSite = ex.TargetSite; if (targetSite != null) { str = string.Format("{0}.{1}", targetSite.DeclaringType, targetSite.Name); } } return str; } protected Exception GetBenmostException(Exception ex) { while (true) { if (ex.InnerException != null) { ex = ex.InnerException; } else { return ex; } } } #endregion }</code></pre></div></div><p>添加Error视图</p><div class="rno-markdown-code"><div class="rno-markdown-code-toolbar"><div class="rno-markdown-code-toolbar-info"><div class="rno-markdown-code-toolbar-item is-type"><span class="is-m-hidden">代码语言：</span>javascript</div></div><div class="rno-markdown-code-toolbar-opt"><div class="rno-markdown-code-toolbar-copy"><i class="icon-copy"></i><span class="is-m-hidden">复制</span></div></div></div><div class="developer-code-block"><pre class="prism-token token line-numbers language-javascript"><code class="language-javascript" style="margin-left:0">@model App.Admin.Controllers.BaseException@{
ViewBag.Title = "异常处理页面";
Layout = "~/Views/Shared/_Index_Layout.cshtml";
}<h2>系统错误</h2>
<div style="text-align:center;">
<table width="100%" class="blueTab" border="0" cellspacing="1" cellpadding="1">
<tr>
<td colspan="3">
<table cellspacing="0" cellpadding="0" width="100%" border="0">
<tbody>
<tr>
<td >
错误处理页面</td>
</tr>
</tbody>
</table>
</td>
</tr>
<tr id="youhaotishi" >
<td colspan="2" align="left">
欢迎您光临本网站！网站运行发生错误，请与管理员联系。错误原因可能如下:
<br />
1.非法访问页面.
<br />
2.您输入的数据错误.
<br />
3.您访问的页面不存在.
<br />
4.内容不存在,或已被删除.
<br />
5.系统忙,请稍候再试.
</td>
</tr>
<tbody id="detailInformation" style="display: none;">
<tr>
<td width="20%" class="alignRight" nowrap>
<strong>出错页面：</strong>
</td>
<td class="alignLeft">
@Html.DisplayFor(model => model.ErrorPageUrl) </td>
</tr>
<tr>
<td class="alignRight" nowrap>
<strong>异常名称：</strong>
</td>
<td class="alignLeft">
@Html.DisplayFor(model => model.ExceptionName) </td>
</tr>
<tr>
<td class="alignRight" nowrap>
<strong>异常信息：</strong>
</td>
<td class="alignLeft">
@Html.DisplayFor(model => model.ExceptionMessage) </td>
</tr>
<tr id="trInnerExceptionName" runat="server">
<td class="alignRight" nowrap>
<strong>内部异常名称：</strong>
</td>
<td class="alignLeft">
@Html.DisplayFor(model => model.InnerExceptionName) </td>
</tr>
<tr id="trInnerExceptionMessage" runat="server">
<td class="alignRight" nowrap>
<strong>内部异常信息：</strong>
</td>
<td class="alignLeft">
@Html.DisplayFor(model => model.InnerExceptionMessage)
</td>
</tr>
<tr id="trExceptionMethod" runat="server">
<td class="alignRight" nowrap>
<strong>方法名称：</strong>
</td>
<td class="alignLeft" style="background-color: #ffffcc;">
@Html.DisplayFor(model => model.TargetSite) </td>
</tr>
<tr id="trExceptionSource" runat="server">
<td class="alignRight" nowrap>
<strong>源文件：</strong>
</td>
<td class="alignLeft" style="background-color: #ffffcc;">
@Html.DisplayFor(model => model.SourceErrorFile)
</td>
</tr>
<tr id="trExceptionRowId" runat="server">
<td class="alignRight" nowrap>
<strong>行号：</strong>
</td>
<td class="alignLeft" style="background-color: #ffffcc; color: Red">
@Html.DisplayFor(model => model.SourceErrorRowID) </td>
</tr>
<tr runat="server" id="trStack" visible="false">
<td class="alignRight">
<strong>堆栈跟踪：</strong>
</td>
<td class="alignLeft" style="background-color: #ffffcc;">
<code>
<pre id="litStack"><textarea name="errormsg" cols="80" rows="30" readonly="readonly">@Html.DisplayFor(model => model.StackInfo) </textarea> </pre>
</code>
</td>
</tr>
</tbody>
</table>
<a id="showMessage" href="#" onclick="ShowErrorMessage();return false;">显示详细信息</a>
</div><script type="text/javascript">
var isShowMessage = true; function ShowErrorMessage() { var obj = document.getElementById("showMessage") var detailInformation = document.getElementById("detailInformation"); var youhaotishi = document.getElementById("youhaotishi"); if (isShowMessage) { obj.innerText = "隐藏详细信息"; isShowMessage = false; detailInformation.style.display = "block"; youhaotishi.style.display = "none"; } else { obj.innerText = "显示详细信息"; isShowMessage = true; detailInformation.style.display = "none"; youhaotishi.style.display = "block"; } }
</script>
