从字符串中获取子字符串 [英] Get substring from string

问题描述

你好，



请原谅我，我是C＃的新手。



我是想知道是否有人可以指出我正确的方向（逻辑上）

可以获得两点之间的所有角色。



ie - i有一个日志文件（由外部应用程序生成的txt文件）

Hi There,

Please forgive me i'm new to C#.

I was wondering if anyone can point me in the right direction (logicwise)
is possible to get all character between two points.

ie - i have a log file (txt file produced by external app)

3/5/2018 12:00 = Critical = xF"CAPTURE BETWEEN HERE"

我只是尝试捕获并将Capture Between Here存储到新的字符串中，而不是整行。



我知道我可以使用子串（x，y）并定义字符的位置，或者使用IF语句但这会改变，我想知道是否有更好的方法捕获和之间的任何值



对不起，我是.net的新手。



谢谢提前



我的尝试：



我试过了IF语句但是有很多日志变量要写if语句。



我尝试使用子字符串位置，但因为日志更改我永远无法捕获正确的值



我尝试过使用正则表达式模式匹配

I'm only try to capture and store the "Capture Between Here" into a new string, not the entire line.

I know i can use substring(x,y) and define location of the chars, or use a IF statement but this changes, i was wondering is there a better method to capture any value between " and "

Sorry i'm new to .net.

Thanks In Advance

What I have tried:

I've tried IF statement but there are to many log variable to write if statements for.

I've tried using substring location but because the log changes i can never capture the correct value

I've tried using regex pattern matching

MatchCollection matches = Regex.Matches(logstring, regexpattern, RegexOptions.IgnoreCase);
foreach (Match match in matches)
{
    if (match.Success)
        StringBuilder1.Append(match.Groups[1].Value);
}

im new

im new

推荐答案

如何做到这一点最终取决于日志文件中的所有可能条目。



如果总是在表格中

How to do this finally depends on all the possible entries in the log file.

If that is always in the form

<date> = <severity> = <prefix><capture>

我会找到第二个'='字符并尝试识别（跳过）前缀。这可以使用字符串搜索功能（当前缀总是具有相同的长度）或正则表达式来完成。



但是：

这取决于日志文件格式（当我对一般格式的假设是正确的时，前缀的格式） 。

I would locate the second '=' character and try to identify (skip) the prefix. This can be done using string search functions (when the prefix always has the same length) or a regular expression.

But again:
It depends on the log file format (the format of the prefix when my assumption about the general format is correct).

引用：

捕获和之间的任何值的方法

method to capture any value between " and "

如果这意味着要捕获的部分始终用双引号括起来，使用正则表达式匹配非常简单。



正则表达式应该是（未经测试）

If that means that the part to be captured is always enclosed by double quotes it is quite simple using a regular expression match.

The regex should be then (untested)

^.+\"(.+)\"

或者只是使用字符串搜索找到每行的双引号。

[/ EDIT]

or just locate the double quotes using string search for each line.
[/EDIT]

谢谢Jochen！那就做到了!!



我使用第一种方法并找到第二个=字符和之后的字符串，然后删除前缀。这给我留下了我追求的价值！日志文件是一致的所以我应该能够重复使用这个值，无论价值如何。



我可能会考虑使用正则表达式，但因为我是一个菜鸟我认为我可能只是让它沉入其中。感谢您抽出时间来欣赏第二双眼睛/大脑。

Thanks Jochen! That Did it!!

I used the first method and located the second "=" character and the string after that, then removed prefix. this left me with values i was after! The log file is consistent so i should be able to reuse this regardless of the values.

I might look at using a regex but since i'm a noob i think i might just let this sink in. Thank you for taking the time to look at this appreciate the second pair of eyes/brains.

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