log4net.Layout.PatternLayout 用 conversion 模…

转换模式名称

效果

a

等价于 appdomain

appdomain

用于输出当产生日志事件时的 AppDomain 名称。

aspnet-cache

指定 %aspnet-cache 时输出所有 cache 项；指定 %aspnet-cache{key} 时只输出 key 指定的项。

该模式对 Compact Framework or Client Profile 不可用。

aspnet-context

指定 %aspnet-context 时输出所有 context 项；指定 %aspnet-context 时只输出 key 指定的项。

该模式对 Compact Framework or Client Profile 不可用。

aspnet-request

指定 %aspnet-request 时输出所有请求参数的项；指定 %aspnet-request{key} 时只输出 key 指定的项。

该模式对 Compact Framework or Client Profile 不可用。

aspnet-session

指定 %aspnet-session 时输出所有 session 项；指定 %aspnet-session{key} 时只输出 key 指定的项。

该模式对 Compact Framework or Client Profile 不可用。

c

等价于 logger

C

等价于 type

class

等价于 type

d

等价于 date

date

以 local time zone 输出日志事件的日期。若输出 universal time 日期要使用 %utcdate 模式。日期格式也可以在模式后用大括号指定，例如，%date{HH:mm:ss,fff} 或 %date{dd MMM yyyy HH:mm:ss,fff}。若没有指定日期格式，则将采用 ISO8601（Iso8601DateFormatter）。日期格式指示器跟 ToString 方法个式化日期时采用时间模式具有相同的语法。

推荐使用 log4net 日期格式化器，能得到更好的输出。通过指定字符串“ABSOLUTE”，“DATE”和“ISO8601”中的一个，分别表示 AbsoluteTimeDateFormatter, DateTimeDateFormatter 和  Iso8601DateFormatter。例如，%date{ISO8601} 或 %date{ABSOLUTE}。

这写专用的日期格式化要比 ToString 更好。

exception

Used to output the exception passed in with the log message.

If an exception object is stored in the logging event it will be rendered into the pattern output with a trailing newline. If there is no exception then nothing will be output and no trailing newline will be appended. It is typical to put a newline before the exception and to have the exception as the last data in the pattern.

F

等价于 file

file

输出发生日志请求的文件名。

警告：产生调用位置信息相当慢。除非执行速度不是问题，否则要避免使用它。

See the note below on the availability of caller location information.

identity

输出当前活跃用户的用户名（Principal.Identity.Name）。

警告：产生调用位置信息相当慢。除非执行速度不是问题，否则要避免使用它。

l

等价于 location

L

等价于 line

location

Used to output location information of the caller which generated the logging event.

位置信息（location information）依赖 CLI 的实现，但通常是由调用方法的完整限定名（fully qualified name）组成，后面跟调用者源文件名和行号。

位置信息很有用。然而，它的产生相当慢。除非执行速度不是问题，否则要避免使用。

See the note below on the availability of caller location information.

level

输出日志事件的级别。

line

输出发生日志请求时的行号。

警告：产生调用位置信息相当慢。除非执行速度不是问题，否则要避免使用它。

See the note below on the availability of caller location information.

logger

输出日志事件的日志器。The logger conversion specifier can be optionally followed by precision specifier, that is a decimal constant in brackets.

If a precision specifier is given, then only the corresponding number of right most components of the logger name will be printed. By default the logger name is printed in full.

例如，若日志器名为 "a.b.c"，模式为 %logger{2}，将输出 "b.c".

m

等价于 message

M

等价于 method

message

输出与日志事件相关联的应用程序提供的信息，也就是你敲入的信息。

mdc

The MDC (old name for the ThreadContext.Properties) is now part of the combined event properties. This pattern is supported for compatibility but is equivalent to property.

method

输出发生日志请求时的方法名。

警告：产生调用位置信息相当慢。除非执行速度不是问题，否则要避免使用它。

See the note below on the availability of caller location information.

n

等价于 newline

newline

输出换行。换行是平台依赖的，各个平台可能不同。

This conversion pattern offers the same performance as using non-portable line separator strings such as "\n", or "\r\n". Thus, it is the preferred way of specifying a line separator.

ndc

输出与生产日志事件线程有关的 NDC（nested diagnostic context）。

p

等价于 level

P

等价于 property

properties

等价于 property

property

Used to output the an event specific property. The key to lookup must be specified within braces and directly following the pattern specifier, e.g. %property{user} would include the value from the property that is keyed by the string 'user'. Each property value that is to be included in the log must be specified separately. Properties are added to events by loggers or appenders. By default the log4net:HostName property is set to the name of machine on which the event was originally logged.

If no key is specified, e.g. %property then all the keys and their values are printed in a comma separated list.

The properties of an event are combined from a number of different contexts. These are listed below in the order in which they are searched.

the event properties

The event has Properties that can be set. These properties are specific to this event only.

the thread properties

The Properties that are set on the current thread. These properties are shared by all events logged on this thread.

the global properties

The Properties that are set globally. These properties are shared by all the threads in the AppDomain.

r

等价于 timestamp

stacktrace

Used to output the stack trace of the logging event The stack trace level specifier may be enclosed between braces. For example, %stacktrace{level}. If no stack trace level specifier is given then 1 is assumed

Output uses the format: type3.MethodCall3 > type2.MethodCall2 > type1.MethodCall1

This pattern is not available for Compact Framework assemblies.

stacktracedetail

Used to output the stack trace of the logging event The stack trace level specifier may be enclosed between braces. For example, %stacktracedetail{level}. If no stack trace level specifier is given then 1 is assumed

Output uses the format: type3.MethodCall3(type param,...) > type2.MethodCall2(type param,...) > type1.MethodCall1(type param,...)

This pattern is not available for Compact Framework assemblies.

t

等价于 thread

timestamp

Used to output the number of milliseconds elapsed since the start of the application until the creation of the logging event.

thread

输出产生日志事件的线程名称。如果没有可用的线程名称，则使用数字。

type

Used to output the fully qualified type name of the caller issuing the logging request. This conversion specifier can be optionally followed by precision specifier, that is a decimal constant in brackets.

If a precision specifier is given, then only the corresponding number of right most components of the class name will be printed. By default the class name is output in fully qualified form.

For example, for the class name "log4net.Layout.PatternLayout", the pattern %type{1} will output "PatternLayout".

警告：产生调用位置信息相当慢。除非执行速度不是问题，否则要避免使用它。

See the note below on the availability of caller location information.

u

等价于 identity

username

输出当前活跃用户的 WindowsIdentity。

警告：产生调用位置信息相当慢。除非执行速度不是问题，否则要避免使用它。

utcdate

Used to output the date of the logging event in universal time. The date conversion specifier may be followed by a date format specifier enclosed between braces. For example, %utcdate{HH:mm:ss,fff} or %utcdate{dd MMM yyyy HH:mm:ss,fff}. If no date format specifier is given then ISO8601 format is assumed (Iso8601DateFormatter).

The date format specifier admits the same syntax as the time pattern string of the ToString.

For better results it is recommended to use the log4net date formatters. These can be specified using one of the strings "ABSOLUTE", "DATE" and "ISO8601" for specifying AbsoluteTimeDateFormatter, DateTimeDateFormatter and respectively Iso8601DateFormatter. For example, %utcdate{ISO8601} or %utcdate{ABSOLUTE}.

These dedicated date formatters perform significantly better than ToString.

w

等价于 username

x

等价于 ndc

X

等价于 mdc

%

连续两个百分号 %% 会输出一个百分号。

格式修饰符

左边对齐

最小宽度

最大宽度

备注

%20logger

false

20

无

若日志器的名称小于 20 个字符，则左边补空格。

%-20logger

true

20

无

若日志器的名称小于 20 个字符，则右边补空格。

%.30logger

NA

无

30

若日志器的名称大于 30 个字符，则截取。

%20.30logger

false

20

30

若日志器的名称小于 20 个字符，则左边补空格。但是，若日志器名称的长度大于 30 个字符，则截取。

%-20.30logger

true

20

30

若日志器的名称小于 20 个字符，则右边补空格。但是，若日志器名称的长度大于 30 个字符，则截取。