I am trying to highlight multiple lines of specific text in a RichTextBox.
Here is my code for highlighting text:
public void HighlightMistakes(RichTextBox richTextBox)
{
string[] phrases = { "Drivers Do Not Match", "Current Does Not Match", "No Drivers Found" };
foreach (var phrase in phrases)
{
int startIndex = 0;
while (startIndex <= richTextBox.TextLength)
{
int phraseStartIndex = richTextBox.Find(phrase, startIndex, RichTextBoxFinds.None);
if (phraseStartIndex != -1)
{
richTextBox.SelectionStart = phraseStartIndex;
richTextBox.SelectionLength = phrase.Length;
richTextBox.SelectionBackColor = Color.Yellow;
}
else break;
startIndex += phraseStartIndex + phrase.Length;
}
}
}
Here is how I add text to RTB and call function above:
foreach (var a in resultList)
{
richTextBox1.AppendText("\n"+a + "\n");
HighlightMistakes(richTextBox1);
}
However, HighlightMistakes doesn't work the way I would like it to. The idea is to highlight all string values specified in phrases array and that doesn't happen every time.
Examples:
I am not sure why some of the lines are skipped and some of them are not.
If you have nothing against a simple Regex method, you can use Regex.Matches to match your list of phrases against the text of your RichTextBox.
Each Match in the collection of Matches contains both the Index (the position inside the text) where the match is found and its Length, so you can simply call .Select(Index, Length) to select a phrase and highlight it.
The pattern used is the string resulting from joining the phrases to match with a Pipe (|).
Each phrase is passed to Regex.Escape(), since the text may contain metacharacters.
If you want to considere the case, remove RegexOptions.IgnoreCase.
using System.Text.RegularExpressions;
string[] phrases = { "Drivers Do Not Match",
"Current Does Not Match",
"No Drivers Found" };
HighlightMistakes(richTextBox1, phrases);
private void HighlightMistakes(RichTextBox rtb, string[] phrases)
{
ClearMistakes(rtb);
string pattern = string.Join("|", phrases.Select(phr => Regex.Escape(phr)));
var matches = Regex.Matches(rtb.Text, pattern, RegexOptions.IgnoreCase);
foreach (Match m in matches) {
rtb.Select(m.Index, m.Length);
rtb.SelectionBackColor = Color.Yellow;
}
}
private void ClearMistakes(RichTextBox rtb)
{
int selStart = rtb.SelectionStart;
rtb.SelectAll();
rtb.SelectionBackColor = rtb.BackColor;
rtb.SelectionStart = selStart;
rtb.SelectionLength = 0;
}
I am providing a textbox for one to enter a Regular Expression to match filenames. I plan to detect any named capture groups that they provide with the Regex method GetGroupNames().
I want to get the expression that they entered inside each named capture group.
As an example, they might enter a regular expression like this:
December (?<FileYear>\d{4}) Records\.xlsx
Is there a method or means to get the sub-expression \d{4} apart from manually parsing the regular expression string?
Here is an ugly brute force extension for parsing without using another Regex to detect the subexpression (or subpattern):
public static string GetSubExpression(this Regex pRegex, string pCaptureName)
{
string sRegex = pRegex.ToString();
string sGroupText = #"(?<" + pCaptureName + ">";
int iStartSearchAt = sRegex.IndexOf(sGroupText) + sGroupText.Length;
string sRemainder = sRegex.Substring(iStartSearchAt);
string sThis;
string sPrev = "";
int iOpenParenCount = 0;
int iEnd = 0;
for (int i = 0; i < sRemainder.Length; i++)
{
sThis = sRemainder.Substring(i, 1);
if (sThis == ")" && sPrev != #"\" && iOpenParenCount == 0)
{
iEnd = i;
break;
}
else if (sThis == ")" && sPrev != #"\")
{
iOpenParenCount--;
}
else if (sThis == "(" && sPrev != #"\")
{
iOpenParenCount++;
}
sPrev = sThis;
}
return sRemainder.Substring(0, iEnd);
}
The usage looks like this:
Regex reFromUser = new Regex(txtFromUser.Text);
string[] asGroupNames = reFromUser.GetGroupNames();
int iItsInt;
foreach (string sGroupName in asGroupNames)
{
if (!Int32.TryParse(sGroupName, out iItsInt)) //don't want numbered groups
{
string sSubExpression = reParts.GetSubExpression(sGroupName);
//Do what I need to do with the sub-expression
}
}
Now, if you would like to generate test or sample data, you can use the NuGet package called "Fare" in the following way after you get a sub-expression:
//Generate test data for it
Fare.Xeger X = new Fare.Xeger(sSubExpression);
string sSample = X.Generate();
This pattern (?<=\(\?<\w+\>)([^)]+) will give you all the named match capture expression with the name of the capture. It uses a negative look behind to make sure the text matched will have a (?<...> before it.
string data = #"December (?<FileYear>\d{4}) Records\.xlsx";
string pattern = #"(?<=\(\?<\w+\>)([^)]+)";
Regex.Matches(data, pattern)
.OfType<Match>()
.Select(mt => mt.Groups[0].Value)
returns one item of
\d{4}
While the data such as (?<FileMonth>[^\s]+)\s+(?<FileYear>\d{4}) Records\.xlsx would return two matches:
[^\s]+
\d{4}
Here is a solution using a regular expression to match the capturing groups in a regular expression. Idea is from this post Using RegEx to balance match parenthesis:
\(\?\<(?<MyGroupName>\w+)\>
(?<MyExpression>
((?<BR>\()|(?<-BR>\))|[^()]*)+
)
\)
or more concisely...
\(\?\<(?<MyGroupName>\w+)\>(?<MyExpression>((?<BR>\()|(?<-BR>\))|[^()]*)+)\)
and to use it might look like this:
string sGetCaptures = #"\(\?\<(?<MyGroupName>\w+)\>(?<MyExpression>((?<BR>\()|(?<-BR>\))|[^()]*)+)\)";
MatchCollection MC = Regex.Matches(txtFromUser.Text, sGetCaptures );
foreach (Match M in MC)
{
string sGroupName = M.Groups["MyGroupName"].Value;
string sSubExpression = M.Groups["MyExpression"].Value;
//Do what I need to do with the sub-expression
MessageBox.Show(sGroupName + ":" + sSubExpression);
}
And for the example in the original question, the message box would return FileYear:\d{4}
It keeps going to the else statement for Missing numbers. It reads if I input "The" but when i input two numbers it says the count is still 0. then will return the else statement instead of going and changing the labels. Why?
protected void submit_Click(object sender, EventArgs e)
{
string input = textbox.Text;
string s = textbox.ToString();
input = input.Trim();
MatchCollection matches = Regex.Matches(s, #"\d+");
string[] result = matches.Cast<Match>()
.Take(2)
.Select(match => match.Value)
.ToArray();
if (input.StartsWith("The") || input.StartsWith("the"))
{
if (matches.Count == 2)
{
alarm.Text = result[0];
server.Text = result[1];
}
else
{
string script = "alert(\"Missing Number(s)!\");";
ScriptManager.RegisterStartupScript(this, GetType(),
"ServerControlScript", script, true);
}
}
}
Regex.Matches.Count works correctly.
You need to replace
string s = textbox.ToString();
with
string s = textbox.Text;
Else, you analyze a different string (the textbox type string).
Also, you can use just one variable for the text box value and trim it when necessary only.
This is how I would do it. I think this way it's much more cleaner and easier to read:
string input = textbox.Text.Trim();
var match = Regex.Match(input, #"^[tT]he\s(\d+)\s(\d+)\b");
if (match.Success && match.Groups.Count == 3)
{
var alarm = match.Groups[1].Value;
var server = match.Groups[2].Value;
}
else
{
string script = "alert(\"Missing Number(s)!\");"; // Or "invalid format".
ScriptManager.RegisterStartupScript(this, GetType(), "ServerControlScript", script, true);
}
You didn't say much about that input string, so you may have to tune that regular expression. I supposed you expect spaces between the terms and ignore anything after the second digit.
String mystring="start i dont know hot text can it to have here important=value5; x=1; important=value2; z=3;";
suggest i want to get the value of "importante" now i know how to do it with a substring, but it has 2 subistring, then how do i get, first one, and after the next? ...??
if it is not posible i want to try it... save the first. and delete since "start" until value5 for next query save the value2...
how to do any of two things?
i get the first value so...
string word = "important=";
int c= mystring.IndexOf(word);
int c2 = word.Length;
for (int i = c+c2; i < mystring.Length; i++)
{
if (mystring[i].ToString() == ";")
{
break;
}
else
{
label1.Text += mystring[i].ToString(); // c#
// label1.setText(label1.getText()+mystring[i].ToString(); //java
}
}
If you want to extract all values you could use a regex:
string input = "start i dont know hot text can it to have here important=value5; x=1; important=value2; z=3;";
Regex regex = new Regex(#"important=(?<value>\w+)");
List<string> values = new List<string>();
MatchCollection matches = regex.Matches(input);
foreach (Match match in matches)
{
string value= match.Groups["value"].Value;
values.Add(value);
}
You can save the values in an array, instead of showing them with MessageBox.
string mystring = "start i dont know hot text can it to have here important=value5; x=1; important=value2; z=3;";
string temp = mystring;
string word = "important=";
while (temp.IndexOf(word) > 0)
{
MessageBox.Show( temp.Substring(temp.IndexOf(word) + word.Length).Split(';')[0]);
temp = temp.Remove(temp.IndexOf(word), word.Length);
}
You can use 2 methods:
String.Remove()
and
String.Replace()
use regular expression, find all the match and reconstruct the string yourself.
Do any of you know of an easy/clean way to find a substring within a string while ignoring some specified characters to find it. I think an example would explain things better:
string: "Hello, -this- is a string"
substring to find: "Hello this"
chars to ignore: "," and "-"
found the substring, result: "Hello, -this"
Using Regex is not a requirement for me, but I added the tag because it feels related.
Update:
To make the requirement clearer: I need the resulting substring with the ignored chars, not just an indication that the given substring exists.
Update 2:
Some of you are reading too much into the example, sorry, i'll give another scenario that should work:
string: "?A&3/3/C)412&"
substring to find: "A41"
chars to ignore: "&", "/", "3", "C", ")"
found the substring, result: "A&3/3/C)41"
And as a bonus (not required per se), it will be great if it's also not safe to assume that the substring to find will not have the ignored chars on it, e.g.: given the last example we should be able to do:
substring to find: "A3C412&"
chars to ignore: "&", "/", "3", "C", ")"
found the substring, result: "A&3/3/C)412&"
Sorry if I wasn't clear before, or still I'm not :).
Update 3:
Thanks to everyone who helped!, this is the implementation I'm working with for now:
http://www.pastebin.com/pYHbb43Z
An here are some tests:
http://www.pastebin.com/qh01GSx2
I'm using some custom extension methods I'm not including but I believe they should be self-explainatory (I will add them if you like)
I've taken a lot of your ideas for the implementation and the tests but I'm giving the answer to #PierrOz because he was one of the firsts, and pointed me in the right direction.
Feel free to keep giving suggestions as alternative solutions or comments on the current state of the impl. if you like.
in your example you would do:
string input = "Hello, -this-, is a string";
string ignore = "[-,]*";
Regex r = new Regex(string.Format("H{0}e{0}l{0}l{0}o{0} {0}t{0}h{0}i{0}s{0}", ignore));
Match m = r.Match(input);
return m.Success ? m.Value : string.Empty;
Dynamically you would build the part [-, ] with all the characters to ignore and you would insert this part between all the characters of your query.
Take care of '-' in the class []: put it at the beginning or at the end
So more generically, it would give something like:
public string Test(string query, string input, char[] ignorelist)
{
string ignorePattern = "[";
for (int i=0; i<ignoreList.Length; i++)
{
if (ignoreList[i] == '-')
{
ignorePattern.Insert(1, "-");
}
else
{
ignorePattern += ignoreList[i];
}
}
ignorePattern += "]*";
for (int i = 0; i < query.Length; i++)
{
pattern += query[0] + ignorepattern;
}
Regex r = new Regex(pattern);
Match m = r.Match(input);
return m.IsSuccess ? m.Value : string.Empty;
}
Here's a non-regex string extension option:
public static class StringExtensions
{
public static bool SubstringSearch(this string s, string value, char[] ignoreChars, out string result)
{
if (String.IsNullOrEmpty(value))
throw new ArgumentException("Search value cannot be null or empty.", "value");
bool found = false;
int matches = 0;
int startIndex = -1;
int length = 0;
for (int i = 0; i < s.Length && !found; i++)
{
if (startIndex == -1)
{
if (s[i] == value[0])
{
startIndex = i;
++matches;
++length;
}
}
else
{
if (s[i] == value[matches])
{
++matches;
++length;
}
else if (ignoreChars != null && ignoreChars.Contains(s[i]))
{
++length;
}
else
{
startIndex = -1;
matches = 0;
length = 0;
}
}
found = (matches == value.Length);
}
if (found)
{
result = s.Substring(startIndex, length);
}
else
{
result = null;
}
return found;
}
}
EDIT: here's an updated solution addressing the points in your recent update. The idea is the same except if you have one substring it will need to insert the ignore pattern between each character. If the substring contains spaces it will split on the spaces and insert the ignore pattern between those words. If you don't have a need for the latter functionality (which was more in line with your original question) then you can remove the Split and if checking that provides that pattern.
Note that this approach is not going to be the most efficient.
string input = #"foo ?A&3/3/C)412& bar A341C2";
string substring = "A41";
string[] ignoredChars = { "&", "/", "3", "C", ")" };
// builds up the ignored pattern and ensures a dash char is placed at the end to avoid unintended ranges
string ignoredPattern = String.Concat("[",
String.Join("", ignoredChars.Where(c => c != "-")
.Select(c => Regex.Escape(c)).ToArray()),
(ignoredChars.Contains("-") ? "-" : ""),
"]*?");
string[] substrings = substring.Split(new[] { ' ' }, StringSplitOptions.RemoveEmptyEntries);
string pattern = "";
if (substrings.Length > 1)
{
pattern = String.Join(ignoredPattern, substrings);
}
else
{
pattern = String.Join(ignoredPattern, substring.Select(c => c.ToString()).ToArray());
}
foreach (Match match in Regex.Matches(input, pattern))
{
Console.WriteLine("Index: {0} -- Match: {1}", match.Index, match.Value);
}
Try this solution out:
string input = "Hello, -this- is a string";
string[] searchStrings = { "Hello", "this" };
string pattern = String.Join(#"\W+", searchStrings);
foreach (Match match in Regex.Matches(input, pattern))
{
Console.WriteLine(match.Value);
}
The \W+ will match any non-alphanumeric character. If you feel like specifying them yourself, you can replace it with a character class of the characters to ignore, such as [ ,.-]+ (always place the dash character at the start or end to avoid unintended range specifications). Also, if you need case to be ignored use RegexOptions.IgnoreCase:
Regex.Matches(input, pattern, RegexOptions.IgnoreCase)
If your substring is in the form of a complete string, such as "Hello this", you can easily get it into an array form for searchString in this way:
string[] searchString = substring.Split(new[] { ' ' },
StringSplitOptions.RemoveEmptyEntries);
This code will do what you want, although I suggest you modify it to fit your needs better:
string resultString = null;
try
{
resultString = Regex.Match(subjectString, "Hello[, -]*this", RegexOptions.IgnoreCase).Value;
}
catch (ArgumentException ex)
{
// Syntax error in the regular expression
}
You could do this with a single Regex but it would be quite tedious as after every character you would need to test for zero or more ignored characters. It is probably easier to strip all the ignored characters with Regex.Replace(subject, "[-,]", ""); then test if the substring is there.
Or the single Regex way
Regex.IsMatch(subject, "H[-,]*e[-,]*l[-,]*l[-,]*o[-,]* [-,]*t[-,]*h[-,]*i[-,]*s[-,]*")
Here's a non-regex way to do it using string parsing.
private string GetSubstring()
{
string searchString = "Hello, -this- is a string";
string searchStringWithoutUnwantedChars = searchString.Replace(",", "").Replace("-", "");
string desiredString = string.Empty;
if(searchStringWithoutUnwantedChars.Contains("Hello this"))
desiredString = searchString.Substring(searchString.IndexOf("Hello"), searchString.IndexOf("this") + 4);
return desiredString;
}
You could do something like this, since most all of these answer require rebuilding the string in some form.
string1 is your string you want to look through
//Create a List(Of string) that contains the ignored characters'
List<string> ignoredCharacters = new List<string>();
//Add all of the characters you wish to ignore in the method you choose
//Use a function here to get a return
public bool subStringExist(List<string> ignoredCharacters, string myString, string toMatch)
{
//Copy Your string to a temp
string tempString = myString;
bool match = false;
//Replace Everything that you don't want
foreach (string item in ignoredCharacters)
{
tempString = tempString.Replace(item, "");
}
//Check if your substring exist
if (tempString.Contains(toMatch))
{
match = true;
}
return match;
}
You could always use a combination of RegEx and string searching
public class RegExpression {
public static void Example(string input, string ignore, string find)
{
string output = string.Format("Input: {1}{0}Ignore: {2}{0}Find: {3}{0}{0}", Environment.NewLine, input, ignore, find);
if (SanitizeText(input, ignore).ToString().Contains(SanitizeText(find, ignore)))
Console.WriteLine(output + "was matched");
else
Console.WriteLine(output + "was NOT matched");
Console.WriteLine();
}
public static string SanitizeText(string input, string ignore)
{
Regex reg = new Regex("[^" + ignore + "]");
StringBuilder newInput = new StringBuilder();
foreach (Match m in reg.Matches(input))
{
newInput.Append(m.Value);
}
return newInput.ToString();
}
}
Usage would be like
RegExpression.Example("Hello, -this- is a string", "-,", "Hello this"); //Should match
RegExpression.Example("Hello, -this- is a string", "-,", "Hello this2"); //Should not match
RegExpression.Example("?A&3/3/C)412&", "&/3C\\)", "A41"); // Should match
RegExpression.Example("?A&3/3/C) 412&", "&/3C\\)", "A41"); // Should not match
RegExpression.Example("?A&3/3/C)412&", "&/3C\\)", "A3C412&"); // Should match
Output
Input: Hello, -this- is a string
Ignore: -,
Find: Hello this
was matched
Input: Hello, -this- is a string
Ignore: -,
Find: Hello this2
was NOT matched
Input: ?A&3/3/C)412&
Ignore: &/3C)
Find: A41
was matched
Input: ?A&3/3/C) 412&
Ignore: &/3C)
Find: A41
was NOT matched
Input: ?A&3/3/C)412&
Ignore: &/3C)
Find: A3C412&
was matched