how do i delete one part of a string? - c#

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.

Related

Replace string if starts with string in List

I have a string that looks like this
s = "<Hello it´s me, <Hi how are you <hay"
and a List
List<string> ValidList= {Hello, hay} I need the result string to be like
string result = "<Hello it´s me, ?Hi how are you <hay"
So the result string will if it starts with an < and the rest bellogs to the list, keep it, otherwise if starts with < but doesn´t bellong to list replaces the H by ?
I tried using the IndexOf to find the position of the < and the if the string after starsWith any of the strings in the List leave it.
foreach (var vl in ValidList)
{
int nextLt = 0;
while ((nextLt = strAux.IndexOf('<', nextLt)) != -1)
{
//is element, leave it
if (!(strAux.Substring(nextLt + 1).StartsWith(vl)))
{
//its not, replace
strAux = string.Format(#"{0}?{1}", strAux.Substring(0, nextLt), strAux.Substring(nextLt + 1, strAux.Length - (nextLt + 1)));
}
nextLt++;
}
}
To give the solution I gave as a comment its proper answer:
Regex.Replace(s, string.Format("<(?!{0})", string.Join("|", ValidList)), "?")
This (obviously) uses regular expressions to replace the unwanted < characters by ?. In order to recognize those characters, we use a negative lookahead expression. For the example word list, this would look like this: (?!Hallo|hay). This will essentially match only if what we are matching is not followed by Hallo or hay. In this case, we are matching < so the full expression becomes <(?!Hallo|hay).
Now we just need to account for the dynamic ValidList by creating the regular expression on the fly. We use string.Format and string.Join there.
Something like this without using RegEx or LINQ
string s = "<Hello it´s me, <Hi how are you <hay";
List<string> ValidList = new List<string>() { "Hello", "hay" };
var arr = s.Split(new[] { '<' }, StringSplitOptions.RemoveEmptyEntries);
for (int i = 0; i < arr.Length; i++)
{
bool flag = false;
foreach (var item in ValidList)
{
if (arr[i].Contains(item))
{
flag = false;
break;
}
else
{
flag = (flag) ? flag : !flag;
}
}
if (flag)
arr[i] = "?" + arr[i];
else
arr[i] = "<" + arr[i];
}
Console.WriteLine(string.Concat(arr));
A possible solution using LINQ.It splits the string using < and checks if the "word" (text until a blank space found) following is in the Valid List,adding < or ? accordingly. Finally,it joins it all:
List<string> ValidList = new List<string>{ "Hello", "hay" };
string str = "<Hello it´s me, <Hi how are you <hay";
var res = String.Join("",str.Split(new char[] { '<' }, StringSplitOptions.RemoveEmptyEntries)
.Select(x => ValidList.Contains(x.Split(' ').First()) ? "<" + x : "?"+x));

Parse a string in c# after reading first and last alphabet

I want to cut a string in c# after reading first and last alphabet.
string name = "20150910000549659ABCD000007348summary.pdf";
string result = "ABCD000007348"; // Something like this
string name = "1234 ABCD000007348 summary.pdf";
After reading 1234 "A" comes and at last "s" comes so I want "ABCD000007348"
Simply use Regex:
string CutString(string input)
{
Match result = Regex.Match(input, #"[a-zA-Z]+[0-9]+");
return result.Value;
}
Since you didn't say if it's always a timestamp at the beginning, I've instead opted to iterate over the string to find the first alphabetical character, rather than hardcoding s.Remove(0, n); where n is however many digits are in a timestamp.
string s = "20150910000549659ABCD000007348summary.pdf";
s = s.Replace("summary.pdf", String.Empty);
int firstLetter = 0;
foreach (char c in s)
{
if (Char.IsLetter(c))
{
firstLetter = s.IndexOf(c);
break;
}
}
s = s.Remove(0, firstLetter);

How remove some special words from a string content?

I have some strings containing code for emoji icons, like :grinning:, :kissing_heart:, or :bouquet:. I'd like to process them to remove the emoji codes.
For example, given:
Hello:grinning: , how are you?:kissing_heart: Are you fine?:bouquet:
I want to get this:
Hello , how are you? Are you fine?
I know I can use this code:
richTextBox2.Text = richTextBox1.Text.Replace(":kissing_heart:", "").Replace(":bouquet:", "").Replace(":grinning:", "").ToString();
However, there are 856 different emoji icons I have to remove (which, using this method, would take 856 calls to Replace()). Is there any other way to accomplish this?
You can use Regex to match the word between :anything:. Using Replace with function you can make other validation.
string pattern = #":(.*?):";
string input = "Hello:grinning: , how are you?:kissing_heart: Are you fine?:bouquet: Are you super fan, for example. :words not to replace:";
string output = Regex.Replace(input, pattern, (m) =>
{
if (m.ToString().Split(' ').Count() > 1) // more than 1 word and other validations that will help preventing parsing the user text
{
return m.ToString();
}
return String.Empty;
}); // "Hello , how are you? Are you fine? Are you super fan, for example. :words not to replace:"
If you don't want to use Replace that make use of a lambda expression, you can use \w, as #yorye-nathan mentioned, to match only words.
string pattern = #":(\w*):";
string input = "Hello:grinning: , how are you?:kissing_heart: Are you fine?:bouquet: Are you super fan, for example. :words not to replace:";
string output = Regex.Replace(input, pattern, String.Empty); // "Hello , how are you? Are you fine? Are you super fan, for example. :words not to replace:"
string Text = "Hello:grinning: , how are you?:kissing_heart: Are you fine?:bouquet:";
i would solve it that way
List<string> Emoj = new List<string>() { ":kissing_heart:", ":bouquet:", ":grinning:" };
Emoj.ForEach(x => Text = Text.Replace(x, string.Empty));
UPDATE - refering to Detail's Comment
Another approach: replace only existing Emojs
List<string> Emoj = new List<string>() { ":kissing_heart:", ":bouquet:", ":grinning:" };
var Matches = Regex.Matches(Text, #":(\w*):").Cast<Match>().Select(x => x.Value);
Emoj.Intersect(Matches).ToList().ForEach(x => Text = Text.Replace(x, string.Empty));
But i'm not sure if it's that big difference for such short chat-strings and it's more important to have code that's easy to read/maintain. OP's question was about reducing redundancy Text.Replace().Text.Replace() and not about the most efficient solution.
I would use a combination of some of the techniques already suggested. Firstly, I'd store the 800+ emoji strings in a database and then load them up at runtime. Use a HashSet to store these in memory, so that we have a O(1) lookup time (very fast). Use Regex to pull out all potential pattern matches from the input and then compare each to our hashed emoji, removing the valid ones and leaving any non-emoji patterns the user has entered themselves...
public class Program
{
//hashset for in memory representation of emoji,
//lookups are O(1), so very fast
private HashSet<string> _emoji = null;
public Program(IEnumerable<string> emojiFromDb)
{
//load emoji from datastore (db/file,etc)
//into memory at startup
_emoji = new HashSet<string>(emojiFromDb);
}
public string RemoveEmoji(string input)
{
//pattern to search for
string pattern = #":(\w*):";
string output = input;
//use regex to find all potential patterns in the input
MatchCollection matches = Regex.Matches(input, pattern);
//only do this if we actually find the
//pattern in the input string...
if (matches.Count > 0)
{
//refine this to a distinct list of unique patterns
IEnumerable<string> distinct =
matches.Cast<Match>().Select(m => m.Value).Distinct();
//then check each one against the hashset, only removing
//registered emoji. This allows non-emoji versions
//of the pattern to survive...
foreach (string match in distinct)
if (_emoji.Contains(match))
output = output.Replace(match, string.Empty);
}
return output;
}
}
public class MainClass
{
static void Main(string[] args)
{
var program = new Program(new string[] { ":grinning:", ":kissing_heart:", ":bouquet:" });
string output = program.RemoveEmoji("Hello:grinning: :imadethis:, how are you?:kissing_heart: Are you fine?:bouquet: This is:a:strange:thing :to type:, but valid :nonetheless:");
Console.WriteLine(output);
}
}
Which results in:
Hello :imadethis:, how are you? Are you fine? This is:a:strange:thing :to type:,
but valid :nonetheless:
You do not have to replace all 856 emoji's. You only have to replace those that appear in the string. So have a look at:
Finding a substring using C# with a twist
Basically you extract all tokens ie the strings between : and : and then replace those with string.Empty()
If you are concerned that the search will return strings that are not emojis such as :some other text: then you could have a hash table lookup to make sure that replacing said found token is appropriate to do.
Finally got around to write something up. I'm combining a couple previously mentioned ideas, with the fact we should only loop over the string once. Based on those requirement, this sound like the perfect job for Linq.
You should probably cache the HashSet. Other than that, this has O(n) performance and only goes over the list once. Would be interesting to benchmark, but this could very well be the most efficient solution.
The approach is pretty straight forwards.
First load all Emoij in a HashSet so we can quickly look them up.
Split the string with input.Split(':') at the :.
Decide if we keep the current element.
If the last element was a match, keep the current element.
If the last element was no match, check if the current element matches.
If it does, ignore it. (This effectively removes the substring from the output).
If it doesn't, append : back and keep it.
Rebuild our string with a StringBuilder.
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
namespace ConsoleApplication1
{
static class Program
{
static void Main(string[] args)
{
ISet<string> emojiList = new HashSet<string>(new[] { "kissing_heart", "bouquet", "grinning" });
Console.WriteLine("Hello:grinning: , ho:w: a::re you?:kissing_heart:kissing_heart: Are you fine?:bouquet:".RemoveEmoji(':', emojiList));
Console.ReadLine();
}
public static string RemoveEmoji(this string input, char delimiter, ISet<string> emojiList)
{
StringBuilder sb = new StringBuilder();
input.Split(delimiter).Aggregate(true, (prev, curr) =>
{
if (prev)
{
sb.Append(curr);
return false;
}
if (emojiList.Contains(curr))
{
return true;
}
sb.Append(delimiter);
sb.Append(curr);
return false;
});
return sb.ToString();
}
}
}
Edit: I did something cool using the Rx library, but then realized Aggregate is the IEnumerable counterpart of Scan in Rx, thus simplifying the code even more.
If efficiency is a concern and to avoid processing "false positives", consider rewriting the string using a StringBuilder while skipping the special emoji tokens:
static HashSet<string> emojis = new HashSet<string>()
{
"grinning",
"kissing_heart",
"bouquet"
};
static string RemoveEmojis(string input)
{
StringBuilder sb = new StringBuilder();
int length = input.Length;
int startIndex = 0;
int colonIndex = input.IndexOf(':');
while (colonIndex >= 0 && startIndex < length)
{
//Keep normal text
int substringLength = colonIndex - startIndex;
if (substringLength > 0)
sb.Append(input.Substring(startIndex, substringLength));
//Advance the feed and get the next colon
startIndex = colonIndex + 1;
colonIndex = input.IndexOf(':', startIndex);
if (colonIndex < 0) //No more colons, so no more emojis
{
//Don't forget that first colon we found
sb.Append(':');
//Add the rest of the text
sb.Append(input.Substring(startIndex));
break;
}
else //Possible emoji, let's check
{
string token = input.Substring(startIndex, colonIndex - startIndex);
if (emojis.Contains(token)) //It's a match, so we skip this text
{
//Advance the feed
startIndex = colonIndex + 1;
colonIndex = input.IndexOf(':', startIndex);
}
else //No match, so we keep the normal text
{
//Don't forget the colon
sb.Append(':');
//Instead of doing another substring next loop, let's just use the one we already have
sb.Append(token);
startIndex = colonIndex;
}
}
}
return sb.ToString();
}
static void Main(string[] args)
{
List<string> inputs = new List<string>()
{
"Hello:grinning: , how are you?:kissing_heart: Are you fine?:bouquet:",
"Tricky test:123:grinning:",
"Hello:grinning: :imadethis:, how are you?:kissing_heart: Are you fine?:bouquet: This is:a:strange:thing :to type:, but valid :nonetheless:"
};
foreach (string input in inputs)
{
Console.WriteLine("In <- " + input);
Console.WriteLine("Out -> " + RemoveEmojis(input));
Console.WriteLine();
}
Console.WriteLine("\r\n\r\nPress enter to exit...");
Console.ReadLine();
}
Outputs:
In <- Hello:grinning: , how are you?:kissing_heart: Are you fine?:bouquet:
Out -> Hello , how are you? Are you fine?
In <- Tricky test:123:grinning:
Out -> Tricky test:123
In <- Hello:grinning: :imadethis:, how are you?:kissing_heart: Are you fine?:bouquet: This is:a:strange:thing :to type:, but valid :nonetheless:
Out -> Hello :imadethis:, how are you? Are you fine? This is:a:strange:thing :to type:, but valid :nonetheless:
Use this code I put up below I think using this function your problem will be solved.
string s = "Hello:grinning: , how are you?:kissing_heart: Are you fine?:bouquet:";
string rmv = ""; string remove = "";
int i = 0; int k = 0;
A:
rmv = "";
for (i = k; i < s.Length; i++)
{
if (Convert.ToString(s[i]) == ":")
{
for (int j = i + 1; j < s.Length; j++)
{
if (Convert.ToString(s[j]) != ":")
{
rmv += s[j];
}
else
{
remove += rmv + ",";
i = j;
k = j + 1;
goto A;
}
}
}
}
string[] str = remove.Split(',');
for (int x = 0; x < str.Length-1; x++)
{
s = s.Replace(Convert.ToString(":" + str[x] + ":"), "");
}
Console.WriteLine(s);
Console.ReadKey();
I'd use extension method like this:
public static class Helper
{
public static string MyReplace(this string dirty, char separator)
{
string newText = "";
bool replace = false;
for (int i = 0; i < dirty.Length; i++)
{
if(dirty[i] == separator) { replace = !replace ; continue;}
if(replace ) continue;
newText += dirty[i];
}
return newText;
}
}
Usage:
richTextBox2.Text = richTextBox2.Text.MyReplace(':');
This method show be better in terms of performance compare to one with Regex
I would split the text with the ':' and then build the string excluding the found emoji names.
const char marker = ':';
var textSections = text.Split(marker);
var emojiRemovedText = string.Empty;
var notMatchedCount = 0;
textSections.ToList().ForEach(section =>
{
if (emojiNames.Contains(section))
{
notMatchedCount = 0;
}
else
{
if (notMatchedCount++ > 0)
{
emojiRemovedText += marker.ToString();
}
emojiRemovedText += section;
}
});

Extract node value from xml resembling string C#

I am having strings like below
<ad nameId="\862094\"></ad>
or comma seprated like below
<ad nameId="\862593\"></ad>,<ad nameId="\862094\"></ad>,<ad nameId="\865599\"></ad>
How to extract nameId value and store in single string like below
string extractedValues ="862094";
or in case of comma seprated string above
string extractedMultipleValues ="862593,862094,865599";
This is what I have started trying with but not sure
string myString = "<ad nameId="\862593\"></ad>,<ad nameId="\862094\"></ad>,<ad
nameId="\865599\"></ad>";
string[] myStringArray = myString .Split(',');
foreach (string str in myStringArray )
{
xd.LoadXml(str);
chkStringVal = xd.SelectSingleNode("/ad/#nameId").Value;
}
Search for:
<ad nameId="\\(\d*)\\"><\/ad>
Replace with:
$1
Note that you must search globally. Example: http://www.regex101.com/r/pL2lX1
Please see code below to extract all numbers in your example:
string value = #"<ad nameId=""\862093\""></ad>,<ad nameId=""\862094\""></ad>,<ad nameId=""\865599\""></ad>";
var matches = Regex.Matches(value, #"(\\\d*\\)", RegexOptions.RightToLeft);
foreach (Group item in matches)
{
string yourMatchNumber = item.Value;
}
Try like this;
string s = #"<ad nameId=""\862094\""></ad>";
if (!(s.Contains(",")))
{
string extractedValues = s.Substring(s.IndexOf("\\") + 1, s.LastIndexOf("\\") - s.IndexOf("\\") - 1);
}
else
{
string[] array = s.Split(new char[] { ',' }, StringSplitOptions.RemoveEmptyEntries);
string extractedMultipleValues = "";
for (int i = 0; i < array.Length; i++)
{
extractedMultipleValues += array[i].Substring(array[i].IndexOf("\\") + 1, array[i].LastIndexOf("\\") - array[i].IndexOf("\\") - 1) + ",";
}
Console.WriteLine(extractedMultipleValues.Substring(0, extractedMultipleValues.Length -1));
}
mhasan, here goes an example of what you need(well almost)
EDITED: complete code (it's a little tricky)
(Sorry for the image but i have some troubles with tags in the editor, i can send the code by email if you want :) )
A little explanation about the code, it replaces all ocurrences of parsePattern in the given string, so if the given string has multiple tags separated by "," the final result will be the numbers separated by "," stored in parse variable....
Hope it helps

Retrieve String Containing Specific substring C#

I am having an output in string format like following :
"ABCDED 0000A1.txt PQRSNT 12345"
I want to retreieve substring(s) having .txt in above string. e.g. For above it should return 0000A1.txt.
Thanks
You can either split the string at whitespace boundaries like it's already been suggested or repeatedly match the same regex like this:
var input = "ABCDED 0000A1.txt PQRSNT 12345 THE.txt FOO";
var match = Regex.Match (input, #"\b([\w\d]+\.txt)\b");
while (match.Success) {
Console.WriteLine ("TEST: {0}", match.Value);
match = match.NextMatch ();
}
Split will work if it the spaces are the seperator. if you use oter seperators you can add as needed
string input = "ABCDED 0000A1.txt PQRSNT 12345";
string filename = input.Split(' ').FirstOrDefault(f => System.IO.Path.HasExtension(f));
filname = "0000A1.txt" and this will work for any extension
You may use c#, regex and pattern, match :)
Here is the code, plug it in try. Please comment.
string test = "afdkljfljalf dkfjd.txt lkjdfjdl";
string ffile = Regex.Match(test, #"\([a-z0-9])+.txt").Groups[1].Value;
Console.WriteLine(ffile);
Reference: regexp
I did something like this:
string subString = "";
char period = '.';
char[] chArString;
int iSubStrIndex = 0;
if (myString != null)
{
chArString = new char[myString.Length];
chArString = myString.ToCharArray();
for (int i = 0; i < myString.Length; i ++)
{
if (chArString[i] == period)
iSubStrIndex = i;
}
substring = myString.Substring(iSubStrIndex);
}
Hope that helps.
First split your string in array using
char[] whitespace = new char[] { ' ', '\t' };
string[] ssizes = myStr.Split(whitespace);
Then find .txt in array...
// Find first element starting with .txt.
//
string value1 = Array.Find(array1,
element => element.Contains(".txt", StringComparison.Ordinal));
Now your value1 will have the "0000A1.txt"
Happy coding.

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