I have the following string (output from sox --info command):
Input File : 'C:\Users\source\repos\dotnetcore\audio\1000.wav'
Channels : 1
Sample Rate : 44100
Precision : 16-bit
Duration : 00:05:11.64 = 13743363 samples = 23373.1 CDDA sectors
File Size : 27.5M
Bit Rate : 706k
Sample Encoding: 16-bit Signed Integer PCM
I need to extract the file path (without the single quote), channels, sample rate etc.
I have a method where I pass in the whole string (the output) and the property I want to extract. Like this:
private static string Extract(string inputStr, string property)
{
string pattern = string.Format(#"\s+{0}\s+: '?(.*)\r\n", property);
Match result = Regex.Match(inputStr, pattern);
if (result.Success)
{
return result.Groups[1].Value;
}
return string.Empty;
}
This almost returns what I need, except for the last single quote in the Input File. How do I not include that in the pattern
Extract(output, "Input File") //returns C:\Users\source\repos\dotnetcore\audio\1000.wav' --> How to remove the last single quote
Extract(output, "Channels") //returns 1 --> Good
Extract(output, "Sample Rate") // returns 44100 --> Good
I have tried these patterns also
\s+Input File\s+: '?(.*)'? //Still returns with the last single quote
\s+Input File\s+: '?(.*)'+ //This works for Input File but doesn't work for other properties
Edit: Based on the original author’s comment and my not inspecting all the lines closely enough
\s+{0}\s*: '?([^\r\n']*)'?
Original:
\s+{0}\s+: '?([^\r\n']*)'?
This is because * is greedy--it will keep pulling as many characters as it can. Because the ? allows 0 or 1 characters, it doesn't stop the * from continuing to pull in characters.
Try the following expression: \s*(?<name>[^:]+?)\s*:\s*(?<value>('[^']+')|.+)
See demo: https://regex101.com/r/w7b2oO/1
A couple of differences:
(?<name>...) gives the capture group a name so that you can reference it by name instead of index
('[^']+')|.+) makes captures values enclosed in a string ('[^']+') or (|) without (.+)
In the following piece of code (C#), I would like to replace the value of the Order and GUID in the ContentType annotation:
[ContentType(
DisplayName = "My First Block",
Order = 133536,
GUID = "0f02e38a-a6e2-4333-9bd1-c61cf573d8d3",
Description = "Just an example block.",
GroupName = "Blocks.Content"
)]
public class MyFirstBlock : BaseBlock
{
[CultureSpecific]
[Display(
Name = "Title",
Order = 100,
Description = "The title",
GroupName = "Information")]
[Required]
public virtual XhtmlString Title { get; set; }
}
I'm using the following regular expressions to find the values:
Order: (?<=Order = )\d{4,}(?=[,)])
GUID: (?<=GUID = \").*(?=\")
And these work but they have some shortcomings. For the Order regex, I would like to not have to look for a minimum of 4 digits. I'd much rather do (?<=Order = )\d*(?=[,)]) so it will also find the right location if the current order value is less than 4 digits or even not entered at all. But this will also match the order in the Display annotation for the Title. I've tried making the expression not greedy, as is the accepted answer in just about every search result I find when googling my question, but that doesn't seem to do anything.
For the GUID, I'm running into the same problem. I can't be sure that there will not be another GUID somewhere in the document, that I don't want to replace. So for this expression the problem is basically the same, I only want to find the value of the first GUID in the document.
Another approach I've tried is to look for the Order and GUID inside the ContentType block, but I've not been able to get that to work.
A little background information to put this question in context: I'm writing a VS Extension that will generate the order number based on the text selected by the user and also replace the GUID with a newly generated GUID. I'm using EnvDTE.TextDocument.ReplacePattern() to replace the value for the order and GUID after they've been generated.
You may use the following solution:
var result = Regex.Replace(
Regex.Replace(input, #"(?s)(\[ContentType\((?:(?!\)]).)*?\bOrder\s*=\s*)\d*(.*?\)])", "${1}<<ORDER>>$2"),
#"(?s)(\[ContentType\((?:(?!\)]).)*?\bGUID\s*=\s*""?)[\w-]*(.*?\)])",
"${1}<<GUID>>$2");
See the C# online demo that shows that the Order and GUID values are only replaced in the ContentType part:
Order = <<ORDER>>,
GUID = "<<GUID>>",
Note that the replacement backreferences are made unambiguous by using curly braces since most probably your replacements will be starting with digits and that could create an invalid group reference.
The pattern matches:
(?s) - enables . to match newlines
(\[ContentType\((?:(?!\)]).)*?\bGUID\s*=\s*"?) - Group 1 capturing:
\[ContentType\( - a [ContentType( substring
(?:(?!\)]).)*? - any char not starting a )] sequence, as few as possible,
\bGUID - a whole word GUID (or Order)
\s*=\s* - a = enclosed with 0+ whitespaces
"? - an optional "
[\w-]* - 0 or more word or - chars
(.*?\)]) - Group 2: any chars as few as possible up to the first )] including them.
We have use the following Regex function to highlight the string and numeric
String Regex function
public string StringRegEx
{
get { return #"#?""""|#?"".*?(?!\\).""|''|'.*?(?!\\).'"; }
}
Numeric Regex function
public string NumberRegEX
{
get { return #"[0-9].*?(?=:[0-9]*)?"; }
}
while using this regex function we have face some issues for highlighting string contains numeric
p1 = 1
p2 = 0.2
In this example, 1 and 2 in p1 and p2 also highlighted. How to skip the number highlighted along with the string?
For a more general approach on how to properly catch things when dealing with a programming language snippet, take a look here.
Your problem might not be "comments in strings, strings in comments" but it is similar, namely "letters in a string that started with a number, numbers in a string that started with a letter" so you'll need a similar approach with pipe-separated regexes for the different matches you wanna have.
A more thorough explanation of this design-pattern is given here.
I fall into a surprising issue.
I loaded a text file in my application and I have some logic which compares the value having µ.
And I realized that even if the texts are same the compare value is false.
Console.WriteLine("μ".Equals("µ")); // returns false
Console.WriteLine("µ".Equals("µ")); // return true
In later line the character µ is copy pasted.
However, these might not be the only characters that are like this.
Is there any way in C# to compare the characters which look the same but are actually different?
Because it is really different symbols even they look the same, first is the actual letter and has char code = 956 (0x3BC) and the second is the micro sign and has 181 (0xB5).
References:
Unicode Character 'GREEK SMALL LETTER MU' (U+03BC)
Unicode Character 'MICRO SIGN' (U+00B5)
So if you want to compare them and you need them to be equal, you need to handle it manually, or replace one char with another before comparison. Or use the following code:
public void Main()
{
var s1 = "μ";
var s2 = "µ";
Console.WriteLine(s1.Equals(s2)); // false
Console.WriteLine(RemoveDiacritics(s1).Equals(RemoveDiacritics(s2))); // true
}
static string RemoveDiacritics(string text)
{
var normalizedString = text.Normalize(NormalizationForm.FormKC);
var stringBuilder = new StringBuilder();
foreach (var c in normalizedString)
{
var unicodeCategory = CharUnicodeInfo.GetUnicodeCategory(c);
if (unicodeCategory != UnicodeCategory.NonSpacingMark)
{
stringBuilder.Append(c);
}
}
return stringBuilder.ToString().Normalize(NormalizationForm.FormC);
}
And the Demo
In many cases, you can normalize both of the Unicode characters to a certain normalization form before comparing them, and they should be able to match. Of course, which normalization form you need to use depends on the characters themselves; just because they look alike doesn't necessarily mean they represent the same character. You also need to consider if it's appropriate for your use case — see Jukka K. Korpela's comment.
For this particular situation, if you refer to the links in Tony's answer, you'll see that the table for U+00B5 says:
Decomposition <compat> GREEK SMALL LETTER MU (U+03BC)
This means U+00B5, the second character in your original comparison, can be decomposed to U+03BC, the first character.
So you'll normalize the characters using full compatibility decomposition, with the normalization forms KC or KD. Here's a quick example I wrote up to demonstrate:
using System;
using System.Text;
class Program
{
static void Main(string[] args)
{
char first = 'μ';
char second = 'µ';
// Technically you only need to normalize U+00B5 to obtain U+03BC, but
// if you're unsure which character is which, you can safely normalize both
string firstNormalized = first.ToString().Normalize(NormalizationForm.FormKD);
string secondNormalized = second.ToString().Normalize(NormalizationForm.FormKD);
Console.WriteLine(first.Equals(second)); // False
Console.WriteLine(firstNormalized.Equals(secondNormalized)); // True
}
}
For details on Unicode normalization and the different normalization forms refer to System.Text.NormalizationForm and the Unicode spec.
They both have different character codes: Refer this for more details
Console.WriteLine((int)'μ'); //956
Console.WriteLine((int)'µ'); //181
Where, 1st one is:
Display Friendly Code Decimal Code Hex Code Description
====================================================================
μ μ μ μ Lowercase Mu
µ µ µ µ micro sign Mu
For the specific example of μ (mu) and µ (micro sign), the latter has a compatibility decomposition to the former, so you can normalize the string to FormKC or FormKD to convert the micro signs to mus.
However, there are lots of sets of characters that look alike but aren't equivalent under any Unicode normalization form. For example, A (Latin), Α (Greek), and А (Cyrillic). The Unicode website has a confusables.txt file with a list of these, intended to help developers guard against homograph attacks. If necessary, you could parse this file and build a table for “visual normalization” of strings.
Search both characters in a Unicode database and see the difference.
One is the Greek small Letter µ and the other is the Micro Sign µ.
Name : MICRO SIGN
Block : Latin-1 Supplement
Category : Letter, Lowercase [Ll]
Combine : 0
BIDI : Left-to-Right [L]
Decomposition : <compat> GREEK SMALL LETTER MU (U+03BC)
Mirror : N
Index entries : MICRO SIGN
Upper case : U+039C
Title case : U+039C
Version : Unicode 1.1.0 (June, 1993)
Name : GREEK SMALL LETTER MU
Block : Greek and Coptic
Category : Letter, Lowercase [Ll]
Combine : 0
BIDI : Left-to-Right [L]
Mirror : N
Upper case : U+039C
Title case : U+039C
See Also : micro sign U+00B5
Version : Unicode 1.1.0 (June, 1993)
EDIT After the merge of this question with How to compare 'μ' and 'µ' in C#
Original answer posted:
"μ".ToUpper().Equals("µ".ToUpper()); //This always return true.
EDIT
After reading the comments, yes it is not good to use the above method because it may provide wrong results for some other type of inputs, for this we should use normalize using full compatibility decomposition as mentioned in wiki. (Thanks to the answer posted by BoltClock)
static string GREEK_SMALL_LETTER_MU = new String(new char[] { '\u03BC' });
static string MICRO_SIGN = new String(new char[] { '\u00B5' });
public static void Main()
{
string Mus = "µμ";
string NormalizedString = null;
int i = 0;
do
{
string OriginalUnicodeString = Mus[i].ToString();
if (OriginalUnicodeString.Equals(GREEK_SMALL_LETTER_MU))
Console.WriteLine(" INFORMATIO ABOUT GREEK_SMALL_LETTER_MU");
else if (OriginalUnicodeString.Equals(MICRO_SIGN))
Console.WriteLine(" INFORMATIO ABOUT MICRO_SIGN");
Console.WriteLine();
ShowHexaDecimal(OriginalUnicodeString);
Console.WriteLine("Unicode character category " + CharUnicodeInfo.GetUnicodeCategory(Mus[i]));
NormalizedString = OriginalUnicodeString.Normalize(NormalizationForm.FormC);
Console.Write("Form C Normalized: ");
ShowHexaDecimal(NormalizedString);
NormalizedString = OriginalUnicodeString.Normalize(NormalizationForm.FormD);
Console.Write("Form D Normalized: ");
ShowHexaDecimal(NormalizedString);
NormalizedString = OriginalUnicodeString.Normalize(NormalizationForm.FormKC);
Console.Write("Form KC Normalized: ");
ShowHexaDecimal(NormalizedString);
NormalizedString = OriginalUnicodeString.Normalize(NormalizationForm.FormKD);
Console.Write("Form KD Normalized: ");
ShowHexaDecimal(NormalizedString);
Console.WriteLine("_______________________________________________________________");
i++;
} while (i < 2);
Console.ReadLine();
}
private static void ShowHexaDecimal(string UnicodeString)
{
Console.Write("Hexa-Decimal Characters of " + UnicodeString + " are ");
foreach (short x in UnicodeString.ToCharArray())
{
Console.Write("{0:X4} ", x);
}
Console.WriteLine();
}
Output
INFORMATIO ABOUT MICRO_SIGN
Hexa-Decimal Characters of µ are 00B5
Unicode character category LowercaseLetter
Form C Normalized: Hexa-Decimal Characters of µ are 00B5
Form D Normalized: Hexa-Decimal Characters of µ are 00B5
Form KC Normalized: Hexa-Decimal Characters of µ are 03BC
Form KD Normalized: Hexa-Decimal Characters of µ are 03BC
________________________________________________________________
INFORMATIO ABOUT GREEK_SMALL_LETTER_MU
Hexa-Decimal Characters of µ are 03BC
Unicode character category LowercaseLetter
Form C Normalized: Hexa-Decimal Characters of µ are 03BC
Form D Normalized: Hexa-Decimal Characters of µ are 03BC
Form KC Normalized: Hexa-Decimal Characters of µ are 03BC
Form KD Normalized: Hexa-Decimal Characters of µ are 03BC
________________________________________________________________
While reading information in Unicode_equivalence I found
The choice of equivalence criteria can affect search results. For instance some typographic ligatures like U+FB03 (ffi), ..... so a search for U+0066 (f) as substring would succeed in an NFKC normalization of U+FB03 but not in NFC normalization of U+FB03.
So to compare equivalence we should normally use FormKC i.e. NFKC normalization or FormKD i.e NFKD normalization.
I was little curious to know more about all the Unicode characters so I made sample which would iterate over all the Unicode character in UTF-16 and I got some results I want to discuss
Information about characters whose FormC and FormD normalized values were not equivalent
Total: 12,118
Character (int value): 192-197, 199-207, 209-214, 217-221, 224-253, ..... 44032-55203
Information about characters whose FormKC and FormKD normalized values were not equivalent
Total: 12,245
Character (int value): 192-197, 199-207, 209-214, 217-221, 224-228, ..... 44032-55203, 64420-64421, 64432-64433, 64490-64507, 64512-64516, 64612-64617, 64663-64667, 64735-64736, 65153-65164, 65269-65274
All the character whose FormC and FormD normalized value were not equivalent, there FormKC and FormKD normalized values were also not equivalent except these characters
Characters: 901 '΅', 8129 '῁', 8141 '῍', 8142 '῎', 8143 '῏', 8157 '῝', 8158 '῞'
, 8159 '῟', 8173 '῭', 8174 '΅'
Extra character whose FormKC and FormKD normalized value were not equivalent, but there FormC and FormD normalized values were equivalent
Total: 119
Characters: 452 'DŽ' 453 'Dž' 454 'dž' 12814 '㈎' 12815 '㈏' 12816 '㈐' 12817 '㈑' 12818 '㈒'
12819 '㈓' 12820 '㈔' 12821 '㈕', 12822 '㈖' 12823 '㈗' 12824 '㈘' 12825 '㈙' 12826 '㈚'
12827 '㈛' 12828 '㈜' 12829 '㈝' 12830 '㈞' 12910 '㉮' 12911 '㉯' 12912 '㉰' 12913 '㉱'
12914 '㉲' 12915 '㉳' 12916 '㉴' 12917 '㉵' 12918 '㉶' 12919 '㉷' 12920 '㉸' 12921 '㉹' 12922 '㉺' 12923 '㉻' 12924 '㉼' 12925 '㉽' 12926 '㉾' 13056 '㌀' 13058 '㌂' 13060 '㌄' 13063 '㌇' 13070 '㌎' 13071 '㌏' 13072 '㌐' 13073 '㌑' 13075 '㌓' 13077 '㌕' 13080 '㌘' 13081 '㌙' 13082 '㌚' 13086 '㌞' 13089 '㌡' 13092 '㌤' 13093 '㌥' 13094 '㌦' 13099 '㌫' 13100 '㌬' 13101 '㌭' 13102 '㌮' 13103 '㌯' 13104 '㌰' 13105 '㌱' 13106 '㌲' 13108 '㌴' 13111 '㌷' 13112 '㌸' 13114 '㌺' 13115 '㌻' 13116 '㌼' 13117 '㌽' 13118 '㌾' 13120 '㍀' 13130 '㍊' 13131 '㍋' 13132 '㍌' 13134 '㍎' 13139 '㍓' 13140 '㍔' 13142 '㍖' .......... ﺋ' 65164 'ﺌ' 65269 'ﻵ' 65270 'ﻶ' 65271 'ﻷ' 65272 'ﻸ' 65273 'ﻹ' 65274'
There are some characters which can not be normalized, they throw ArgumentException if tried
Total:2081
Characters(int value): 55296-57343, 64976-65007, 65534
This links can be really helpful to understand what rules govern for Unicode equivalence
Unicode_equivalence
Unicode_compatibility_characters
Most likely, there are two different character codes that make (visibly) the same character. While technically not equal, they look equal. Have a look at the character table and see whether there are multiple instances of that character. Or print out the character code of the two chars in your code.
You ask "how to compare them" but you don't tell us what you want to do.
There are at least two main ways to compare them:
Either you compare them directly as you are and they are different
Or you use Unicode Compatibility Normalization if your need is for a comparison that finds them to match.
There could be a problem though because Unicode compatibility normalization will make many other characters compare equal. If you want only these two characters to be treated as alike you should roll your own normalization or comparison functions.
For a more specific solution we need to know your specific problem. What is the context under which you came across this problem?
If I would like to be pedantic, I would say that your question doesn't make sense, but since we are approaching christmas and the birds are singing, I'll proceed with this.
First off, the 2 entities that you are trying to compare are glyphs, a glyph is part of a set of glyphs provided by what is usually know as a "font", the thing that usually comes in a ttf, otf or whatever file format you are using.
The glyphs are a representation of a given symbol, and since they are a representation that depends on a specific set, you can't just expect to have 2 similar or even "better" identical symbols, it's a phrase that doesn't make sense if you consider the context, you should at least specify what font or set of glyphs you are considering when you formulate a question like this.
What is usually used to solve a problem similar to the one that you are encountering, it's an OCR, essentially a software that recognize and compares glyphs, If C# provides an OCR by default I don't know that, but it's generally a really bad idea if you don't really need an OCR and you know what to do with it.
You can possibly end up interpreting a physics book as an ancient greek book without mentioning the fact that OCR are generally expensive in terms of resources.
There is a reason why those characters are localized the way they are localized, just don't do that.
It's possible to draw both of chars with the same font style and size with DrawString method. After two bitmaps with symbols has been generated, it's possible to compare them pixel by pixel.
Advantage of this method is that you can compare not only absolute equal charcters, but similar too (with definite tolerance).
I want to Find roman numbers inside string (numbers below 20 is enough) and split the string based on roman numbers
eg:user input is :
Whats your name?i)My name is C# ii)My name is ROR iii)My Name is Java
i want to do something like
Whats your name?
i)My name is C#
ii)My name is ROR
iii)My Name is Java
Edit:this is to format the optional questions..so options wont go no more than 5 or 6..
This code:
string input = "I. Some text. II. Some text... V. Some stupid text. XVII. Eshe kakaya-to hernya...";
Regex r = new Regex(#"\bx{0,3}(i{1,3}|i[vx]|vi{0,3})\b", RegexOptions.IgnoreCase);
string result = r.Replace(input, new MatchEvaluator(e => Environment.NewLine + e.Value)).Trim();
Result:
I. Some text.
II. Some text...
V. Some stupid text.
XVII. Eshe kakaya-to hernya...
Regex.Split(yourstring, #"(?=\b\w+\))")
should do what you want.
Example:
var s = "Whats your name?i)My name is C# ii)My name is ROR iii)My Name is Java XX)foo ix)barv x)foobar";
Regex.Split(s, #"(?=\b\w+\))").Dump();
Output:
Note that you can't have a ) in your text. You could use (?=\b[ivxIXV]+\)) as alternative then if you want, but I think you should keep it simple.