This question already has answers here:
Replace the last occurrence of a word in a string - C#
(7 answers)
Closed 4 years ago.
I have the following code:
string group = "1,2,3,4,5";
And I need to find the last comma in the group (which in this case is between 4 and 5) and replace it with the word "AND". Do I need to use LINQ for this? If so, how?
No need to use LINQ, just use LastIndexOf
string str = "1,2,3,4,5";
int pos = str.LastIndexOf(',');
string result = str.Substring(0, pos) + " and " + str.Substring(pos + 1);
I believe the following will work, though you might want to add a check if group even contains a comma:
string group = "1,2,3,4,5";
int i = group.LastIndexOf(",");
string str = group.Substring(0, i) + " and " + group.Substring(i + 1);
you can use a normal for loop for this
public static void Main(string[] args)
{
string str = "1,2,3,4,5";
for (int i=str.Length - 1; i>=0; i--) {
if (str[i] == ',') {
str = str.Substring(0, i+1) + " and " + str.Substring(i + 1);
break;
}
}
Console.WriteLine(str);
}
output of the program is
1,2,3,4, and 5
Neat and clean and on point.
public static void Main(string[] args)
{
var res = ReplaceLastOccurrence("1,2,3,4,5", ",", " and ");
Console.WriteLine(res);
}
public static string ReplaceLastOccurrence(string Source, string Find, string Replace)
{
int place = Source.LastIndexOf(Find);
if(place == -1)
return Source;
string result = Source.Remove(place, Find.Length).Insert(place, Replace);
return result;
}
Fiddle Output:
1,2,3,4 and 5
Related
I need to be able to extract a string between 2 tags for example: "00002" from "morenonxmldata<tag1>0002</tag1>morenonxmldata"
I am using C# and .NET 3.5.
Regex regex = new Regex("<tag1>(.*)</tag1>");
var v = regex.Match("morenonxmldata<tag1>0002</tag1>morenonxmldata");
string s = v.Groups[1].ToString();
Or (as mentioned in the comments) to match the minimal subset:
Regex regex = new Regex("<tag1>(.*?)</tag1>");
Regex class is in System.Text.RegularExpressions namespace.
Solution without need of regular expression:
string ExtractString(string s, string tag) {
// You should check for errors in real-world code, omitted for brevity
var startTag = "<" + tag + ">";
int startIndex = s.IndexOf(startTag) + startTag.Length;
int endIndex = s.IndexOf("</" + tag + ">", startIndex);
return s.Substring(startIndex, endIndex - startIndex);
}
A Regex approach using lazy match and back-reference:
foreach (Match match in Regex.Matches(
"morenonxmldata<tag1>0002</tag1>morenonxmldata<tag2>abc</tag2>asd",
#"<([^>]+)>(.*?)</\1>"))
{
Console.WriteLine("{0}={1}",
match.Groups[1].Value,
match.Groups[2].Value);
}
Extracting contents between two known values can be useful for later as well. So why not create an extension method for it. Here is what i do, Short and simple...
public static string GetBetween(this string content, string startString, string endString)
{
int Start=0, End=0;
if (content.Contains(startString) && content.Contains(endString))
{
Start = content.IndexOf(startString, 0) + startString.Length;
End = content.IndexOf(endString, Start);
return content.Substring(Start, End - Start);
}
else
return string.Empty;
}
string input = "Exemple of value between two string FirstString text I want to keep SecondString end of my string";
var match = Regex.Match(input, #"FirstString (.+?) SecondString ").Groups[1].Value;
To get Single/Multiple values without regular expression
// For Single
var value = inputString.Split("<tag1>", "</tag1>")[1];
// For Multiple
var values = inputString.Split("<tag1>", "</tag1>").Where((_, index) => index % 2 != 0);
For future reference, I found this code snippet at http://www.mycsharpcorner.com/Post.aspx?postID=15 If you need to search for different "tags" it works very well.
public static string[] GetStringInBetween(string strBegin,
string strEnd, string strSource,
bool includeBegin, bool includeEnd)
{
string[] result ={ "", "" };
int iIndexOfBegin = strSource.IndexOf(strBegin);
if (iIndexOfBegin != -1)
{
// include the Begin string if desired
if (includeBegin)
iIndexOfBegin -= strBegin.Length;
strSource = strSource.Substring(iIndexOfBegin
+ strBegin.Length);
int iEnd = strSource.IndexOf(strEnd);
if (iEnd != -1)
{
// include the End string if desired
if (includeEnd)
iEnd += strEnd.Length;
result[0] = strSource.Substring(0, iEnd);
// advance beyond this segment
if (iEnd + strEnd.Length < strSource.Length)
result[1] = strSource.Substring(iEnd
+ strEnd.Length);
}
}
else
// stay where we are
result[1] = strSource;
return result;
}
I strip before and after data.
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Text.RegularExpressions;
namespace testApp
{
class Program
{
static void Main(string[] args)
{
string tempString = "morenonxmldata<tag1>0002</tag1>morenonxmldata";
tempString = Regex.Replace(tempString, "[\\s\\S]*<tag1>", "");//removes all leading data
tempString = Regex.Replace(tempString, "</tag1>[\\s\\S]*", "");//removes all trailing data
Console.WriteLine(tempString);
Console.ReadLine();
}
}
}
Without RegEx, with some must-have value checking
public static string ExtractString(string soapMessage, string tag)
{
if (string.IsNullOrEmpty(soapMessage))
return soapMessage;
var startTag = "<" + tag + ">";
int startIndex = soapMessage.IndexOf(startTag);
startIndex = startIndex == -1 ? 0 : startIndex + startTag.Length;
int endIndex = soapMessage.IndexOf("</" + tag + ">", startIndex);
endIndex = endIndex > soapMessage.Length || endIndex == -1 ? soapMessage.Length : endIndex;
return soapMessage.Substring(startIndex, endIndex - startIndex);
}
public string between2finer(string line, string delimiterFirst, string delimiterLast)
{
string[] splitterFirst = new string[] { delimiterFirst };
string[] splitterLast = new string[] { delimiterLast };
string[] splitRes;
string buildBuffer;
splitRes = line.Split(splitterFirst, 100000, System.StringSplitOptions.RemoveEmptyEntries);
buildBuffer = splitRes[1];
splitRes = buildBuffer.Split(splitterLast, 100000, System.StringSplitOptions.RemoveEmptyEntries);
return splitRes[0];
}
private void button1_Click(object sender, EventArgs e)
{
string manyLines = "Received: from exim by isp2.ihc.ru with local (Exim 4.77) \nX-Failed-Recipients: rmnokixm#gmail.com\nFrom: Mail Delivery System <Mailer-Daemon#isp2.ihc.ru>";
MessageBox.Show(between2finer(manyLines, "X-Failed-Recipients: ", "\n"));
}
I have a program, in which you can input a string. But I want text between quotes " " to be removed.
Example:
in: Today is a very "nice" and hot day.
out: Today is a very "" and hot day.
Console.WriteLine("Enter text: ");
text = Console.ReadLine();
int letter;
string s = null;
string s2 = null;
for (s = 0; s < text.Length; letter++)
{
if (text[letter] != '"')
{
s = s + text[letter];
}
else if (text[letter] == '"')
{
s2 = s2 + letter;
letter++;
(text[letter] != '"')
{
s2 = s2 + letter;
letter++;
}
}
}
I don't know how to write the string without text between quotes to the console.
I am not allowed to use a complex method like regex.
This should do the trick. It checks every character in the string for quotes.
If it finds quotes then sets a quotesOpened flag as true, so it will ignore any subsequent character.
When it encounters another quotes, it sets the flag to false, so it will resume copying the characters.
Console.WriteLine("Enter text: ");
text = Console.ReadLine();
int letterIndex;
string s2 = "";
bool quotesOpened = false;
for (letterIndex= 0; letterIndex< text.Length; letterIndex++)
{
if (text[letterIndex] == '"')
{
quotesOpened = !quotesOpened;
s2 = s2 + text[letterIndex];
}
else
{
if (!quotesOpened)
s2 = s2 + text[letterIndex];
}
}
Hope this helps!
A take without regular expressions, which I like better, but okay:
string input = "abc\"def\"ghi";
string output = input;
int firstQuoteIndex = input.IndexOf("\"");
if (firstQuoteIndex >= 0)
{
int secondQuoteIndex = input.IndexOf("\"", firstQuoteIndex + 1);
if (secondQuoteIndex >= 0)
{
output = input.Substring(0, firstQuoteIndex + 1) + input.Substring(secondQuoteIndex);
}
}
Console.WriteLine(output);
What it does:
It searches for the first occurrence of "
Then it searches for the second occurrence of "
Then it takes the first part, including the first " and the second part, including the second "
You could improve this yourself by searching until the end of the string and replace all occurrences. You have to remember the new 'first index' you have to search on.
string text = #" Today is a very ""nice"" and hot day. Second sentense with ""text"" test";
Regex r = new Regex("\"([^\"]*)\"");
var a = r.Replace(text,string.Empty);
Please try this.
First we need to split string and then remove odd items:
private static String Remove(String s)
{
var rs = s.Split(new[] { '"' }).ToList();
return String.Join("\"\"", rs.Where(_ => rs.IndexOf(_) % 2 == 0));
}
static void Main(string[] args)
{
var test = Remove("hello\"world\"\"yeah\" test \"fhfh\"");
return;
}
This would be a possible solution:
String cmd = "This is a \"Test\".";
// This is a "".
String newCmd = cmd.Split('\"')[0] + "\"\"" + cmd.Split('\"')[2];
Console.WriteLine(newCmd);
Console.Read();
You simply split the text at " and then add both parts together and add the old ". Not a very nice solution, but it works anyway.
€dit:
cmd[0] = "This is a "
cmd[1] = "Test"
cmd[2] = "."
You can do it like this:
Console.WriteLine("Enter text: ");
var text = Console.ReadLine();
var skipping = false;
var result = string.Empty;
foreach (var c in text)
{
if (!skipping || c == '"') result += c;
if (c == '"') skipping = !skipping;
}
Console.WriteLine(result);
Console.ReadLine();
The result string is created by adding characters from the original string as long we are not between quotes (using the skipping variable).
Take all indexes of quotes remove the text between quotes using substring.
static void Main(string[] args)
{
string text = #" Today is a very ""nice"" and hot day. Second sentense with ""text"" test";
var foundIndexes = new List<int>();
foundIndexes.Add(0);
for (int i = 0; i < text.Length; i++)
{
if (text[i] == '"')
foundIndexes.Add(i);
}
string result = "";
for(int i =0; i<foundIndexes.Count; i+=2)
{
int length = 0;
if(i == foundIndexes.Count - 1)
{
length = text.Length - foundIndexes[i];
}
else
{
length = foundIndexes[i + 1] - foundIndexes[i]+1;
}
result += text.Substring(foundIndexes[i], length);
}
Console.WriteLine(result);
Console.ReadKey();
}
Output: Today is a very "" and hot day. Second sentense with "" test";
Here dotNetFiddle
This question already has answers here:
Closed 11 years ago.
Possible Duplicate:
How do I replace the first instance of a string in .NET?
Let's say I have the string:
string s = "Hello world.";
how can I replace the first o in the word Hello for let's say Foo?
In other words I want to end up with:
"HellFoo world."
I know how to replace all the o's but I want to replace just the first one
I think you can use the overload of Regex.Replace to specify the maximum number of times to replace...
var regex = new Regex(Regex.Escape("o"));
var newText = regex.Replace("Hello World", "Foo", 1);
public string ReplaceFirst(string text, string search, string replace)
{
int pos = text.IndexOf(search);
if (pos < 0)
{
return text;
}
return text.Substring(0, pos) + replace + text.Substring(pos + search.Length);
}
here is an Extension Method that could also work as well per VoidKing request
public static class StringExtensionMethods
{
public static string ReplaceFirst(this string text, string search, string replace)
{
int pos = text.IndexOf(search);
if (pos < 0)
{
return text;
}
return text.Substring(0, pos) + replace + text.Substring(pos + search.Length);
}
}
There are a number of ways that you could do this, but the fastest might be to use IndexOf to find the index position of the letter you want to replace and then substring out the text before and after what you want to replace.
if (s.Contains("o"))
{
s = s.Remove(s.IndexOf('o')) + "Foo" + s.Substring(s.IndexOf('o') + 1);
}
I am using the following C# code to modify a lowercase letter to uppercase after a single quote:
public virtual string FirstName
{
get { return _firstName; }
set
{
if (value != null)
{
int pos = value.IndexOf("'", 0);
int strlength = value.Length - 1;
if (pos >= 0 && pos != strlength)
{
string temp = value[pos + 1].ToString();
temp = temp.ToUpper();
value = value.Remove(pos + 1, 1);
value = value.Insert(pos + 1, temp);
}
}
}
}
To me this looks like overkill. Is there an easier way to achieve the desired result:
Value: Mc'donald
Expected: Mc'Donald
here is without regex
int pos = data.IndexOf("'");
if (pos >= 0 && pos < data.Length - 1)
{
StringBuilder sbl = new StringBuilder(data);
sbl[pos + 1] = char.ToUpper(sbl[pos + 1]);
data = sbl.ToString();
}
Since you're open to Regex, would this overload of the Regex.Replace do what you need?
Regex.Replace Method (String, MatchEvaluator)
Here's a modified version of the example given at the link above. I've changed it to use the '\w pattern and to return the match in upper case.
using System;
using System.Text.RegularExpressions;
class RegExSample
{
static string CapText(Match m)
{
// Return the match in upper case
return m.ToString().ToUpperInvariant();
}
static void Main()
{
string text = "Mc'donald";
System.Console.WriteLine("text=[" + text + "]");
Regex rx = new Regex(#"'\w");
string result = rx.Replace(text, new MatchEvaluator(RegExSample.CapText));
System.Console.WriteLine("result=[" + result + "]");
}
}
Perhaps regular expressions?
string value = "Mc'donald";
string found = Regex.Match(value, "'[\\w]").Value;
string result = value.Replace(found, found.ToUpper());
Console.WriteLine(result); // Mc'Donald
This question already has answers here:
Closed 11 years ago.
Possible Duplicate:
How do I replace the first instance of a string in .NET?
Let's say I have the string:
string s = "Hello world.";
how can I replace the first o in the word Hello for let's say Foo?
In other words I want to end up with:
"HellFoo world."
I know how to replace all the o's but I want to replace just the first one
I think you can use the overload of Regex.Replace to specify the maximum number of times to replace...
var regex = new Regex(Regex.Escape("o"));
var newText = regex.Replace("Hello World", "Foo", 1);
public string ReplaceFirst(string text, string search, string replace)
{
int pos = text.IndexOf(search);
if (pos < 0)
{
return text;
}
return text.Substring(0, pos) + replace + text.Substring(pos + search.Length);
}
here is an Extension Method that could also work as well per VoidKing request
public static class StringExtensionMethods
{
public static string ReplaceFirst(this string text, string search, string replace)
{
int pos = text.IndexOf(search);
if (pos < 0)
{
return text;
}
return text.Substring(0, pos) + replace + text.Substring(pos + search.Length);
}
}
There are a number of ways that you could do this, but the fastest might be to use IndexOf to find the index position of the letter you want to replace and then substring out the text before and after what you want to replace.
if (s.Contains("o"))
{
s = s.Remove(s.IndexOf('o')) + "Foo" + s.Substring(s.IndexOf('o') + 1);
}