Okay, lets say I have a string:
string text = "one|two|three";
If I do string[] texts = text.Split('|'); I will end up with a string array of three objects. However, this isn't what I want. What I actually want is to split the string only once... so the two arrays I could would be this:
one
two|three
Additionally, is there a way to do a single split with the last occurrence in a string? So I get:
one|two
three
As well, is there a way to split by a string, instead of a character? So I could do Split("||")
Split method takes a count as parameter, you can pass 2 in that position, which basically says that you're interested in only 2 elements maximum. You'll get the expected result.
For second question: There is no built in way AFAIK. You may need to implement it yourself by splitting all and joining first and second back.
C#'s String.Split() can take a second argument that can define the number of elements to return:
string[] texts = text.Split(new char[] { '|' }, 2);
For your first scenario, you can pass a parameter of how many strings to split into.
var text = "one|two|three";
var result = text.Split(new char[] { '|' }, 2);
Your second scenario requires a little more magic.
var text = "one|two|three";
var list = text.Split('|');
var result = new string[] { string.Join("|", list, 0, list.Length - 1), list[list.Length - 1] };
Code has not been verified to check results before using.
Well, I took it as a challenge to do your second one in one line. The result is... not pretty, mostly because it's surprisingly difficult to reverse a string and keep it as a string.
string text = "one|two|three";
var result = new String(text.Reverse().ToArray()).Split(new char[] {'|'}, 2).Reverse().Select(c => new String(c.Reverse().ToArray()));
Basically, you reverse it, then follow the same procedure as the first one, then reverse each individual one, as well as the resulting array.
You can simply do like this as well...
//To split at first occurence of '|'
if(text.Containts('|')){
beginning = text.subString(0,text.IndexOf('|'));
ending = text.subString(text.IndexOf('|');
}
//To split at last occurence of '|'
if(text.Contains('|')){
beginning = text.subString(0,text.LastIndexOf('|'));
ending = text.subString(text.LastIndexOf('|');
}
Second question was fun. I solved it this way:
string text = "one|two|three";
var result =
new []
{
string.Concat(text.ToCharArray().TakeWhile((c, i) => i <= text.LastIndexOf("|"))),
string.Concat(text.ToCharArray().SkipWhile((c, i) => i <= text.LastIndexOf("|")))
};
Related
So I have a server that receives a connection with the message being converted to a string, I then have this string split between by the spaces
So you have a line:
var line = "hello world my name is bob";
And you don't want "world" or "is", so you want:
"hello my name bob"
If you split to a list, remove the things you don't want and recombine to a line, you won't have extraneous spaces:
var list = line.Split().ToList();
list.Remove("world");
list.Remove("is");
var result = string.Join(" ", list);
Or if you know the exact index positions of your list items, you can use RemoveAt, but remove them in order from highest index to lowest, because if you e.g. want to remove 1 and 4, removing 1 first will mean that the 4 you wanted to remove is now in index 3.. Example:
var list = line.Split().ToList();
list.RemoveAt(4); //is
list.RemoveAt(1); //world
var result = string.Join(" ", list);
If you're seeking a behavior that is like string.Replace, which removes all occurrences, you can use RemoveAll:
var line = "hello is world is my is name is bob";
var list = line.Split().ToList();
list.RemoveAll(w => w == "is"); //every occurence of "is"
var result = string.Join(" ", list);
You could remove the empty space using TrimStart() method.
Something like this:
string text = "Hello World";
string[] textSplited = text.Split(' ');
string result = text.Replace(textSplited[0], "").TrimStart();
Assuming that you only want to remove the first word and not all repeats of it, a much more efficient way is to use the overload of split that lets you control the maximum number of splits (the argument is the maximum number of results, which is one more than the maximum number of splits):
string[] arguments = line.Split(new[] { ' ' }, 2, StringSplitOptions.RemoveEmptyEntries); // split only once
User.data = arguments.Skip(1).FirstOrDefault();
arguments[1] does the right thing when there are "more" arguments, but throw IndexOutOfRangeException if the number of words is zero or one. That could be fixed without LINQ by (arguments.Length > 1)? arguments[1]: string.Empty
If you're just removing the first word of a string, you don't need to use Split at all; doing a Substring after you found the space will be more efficient.
var line = ...
var idx = line.IndexOf(' ')+1;
line = line.Substring(idx);
or in recent C# versions
line = line[idx..];
I have some code that will take in a string from console in [0,0,0,0] format. I then want to split it into an array but leave the [] and only take the numbers. How do i do this? This is what i have, i thought i could split it all and remove the brackets after but it doesnt seem to take the brackets and rather just leaves a null space. is there a way to split from index 1 to -1?
input = Console.ReadLine();
Char[] splitChars = {'[',',',']'};
List<string> splitString = new List<string>(input.Split(splitChars));
Console.WriteLine("[" + String.Join(",", splitString) + "]");
Console.ReadKey();
I love using LinqPad for such tasks, because you can use Console.WriteLine() to get the details of a result like so:
It becomes obvious that you have empty entries, i.e. "" at the beginning and the end. You want to remove those with the overloaded funtion that takes StringSplitOptions.RemoveEmptyEntries [MSDN]:
List<string> splitString = new List<string>(input.Split(splitChars, StringSplitOptions.RemoveEmptyEntries));
Result:
Have an assignment to allow a user to input a word in C# and then display that word with the first and third characters changed to uppercase. Code follows:
namespace Capitalizer
{
class Program
{
static void Main(string[] args)
{
string text = Console.ReadLine();
char[] delimiterChars = { ' ' };
string[] words = text.Split(delimiterChars);
string Upper = text.ToUpper();
Console.WriteLine(Upper);
Console.ReadKey();
}
}
}
This of course generates the entire word in uppercase, which is not what I want. I can't seem to make text.ToUpper(0,2) work, and even then that'd capitalize the first three letters. Only solution I can think of now that would make the word appear on one line (and I don't know if it works) is to move the capitalized letters and lowercase letters into a character array and try to get that to print all values in a modified order.
The simplest way I can think of to address your exact question as described — to convert to upper case the first and third characters of the input — would be something like the following:
StringBuilder sb = new StringBuilder(text);
sb[0] = char.ToUpper(sb[0]);
sb[2] = char.ToUpper(sb[2]);
text = sb.ToString();
The StringBuilder class is essentially a mutable string object, so when doing these kinds of operations is the most fluid way to approach the problem, as it provides the most straightforward conversions to and from, as well as the full range of string operations. Changing individual characters is easy in many data structures, but insertions, deletions, appending, formatting, etc. all also come with StringBuilder, so it's a good habit to use that versus other approaches.
But frankly, it's hard to see how that's a useful operation. I can't help but wonder if you have stated the requirements incorrectly and there's something more to this question than is seen here.
You could use LINQ:
var upperCaseIndices = new[] { 0, 2 };
var message = "hello";
var newMessage = new string(message.Select((c, i) =>
upperCaseIndices.Contains(i) ? Char.ToUpper(c) : c).ToArray());
Here is how it works. message.Select (inline LINQ query) selects characters from message one by one and passes into selector function:
upperCaseIndices.Contains(i) ? Char.ToUpper(c) : c
written as C# ?: shorthand syntax for if. It reads as "If index is present in the array, then select upper case character. Otherwise select character as is."
(c, i) => condition
is a lambda expression. See also:
Understand Lambda Expressions in 3 minutes
The rest is very simple - represent result as array of characters (.ToArray()), and create a new string based off that (new string(...)).
Only solution I can think of now that would make the word appear on one line (and I don't know if it works) is to move the capitalized letters and lowercase letters into a character array and try to get that to print all values in a modified order.
That seems a lot more complicated than necessary. Once you have a character array, you can simply change the elements of that character array. In a separate function, it would look something like
string MakeFirstAndThirdCharacterUppercase(string word) {
var chars = word.ToCharArray();
chars[0] = chars[0].ToUpper();
chars[2] = chars[2].ToUpper();
return new string(chars);
}
My simple solution:
string text = Console.ReadLine();
char[] delimiterChars = { ' ' };
string[] words = text.Split(delimiterChars);
foreach (string s in words)
{
char[] chars = s.ToCharArray();
chars[0] = char.ToUpper(chars[0]);
if (chars.Length > 2)
{
chars[2] = char.ToUpper(chars[2]);
}
Console.Write(new string(chars));
Console.Write(' ');
}
Console.ReadKey();
I got a string
string newString = "[17, Appliance]";
how can I put the 17 and Appliance in two separate variables while ignoring the , and the [ and ]?
I tried looping though it but the loop doesn't stop when it reaches the ,, not to mention it separated 1 & 7 instead of reading it as 17.
For example, you could use this:
newString.Split(new[] {'[', ']', ' ', ','}, StringSplitOptions.RemoveEmptyEntries);
This is another option, even though I wouldn't go with it, especially if you might have more than one [something, anothersomething] in the string.
But there you go:
string newString = "assuming you might [17, Appliance] have it like this";
int first = newString.IndexOf('[')+1; // location of first after the `[`
int last = newString.IndexOf(']'); // location of last before the ']'
var parts = newString.Substring(first, last-first).Split(','); // an array of 2
var int_bit = parts.First ().Trim(); // you could also go with parts[0]
var string_bit = parts.Last ().Trim(); // and parts[1]
This may not be the most performant method, but I'd go with it for ease of understanding.
string newString = "[17, Appliance]";
newString = newString.Replace("[", "").Replace("]",""); // Remove the square brackets
string[] results = newString.Split(new string[] { ", " }, StringSplitOptions.RemoveEmptyEntries); // Split the string
// If your string is always going to contain one number and one string:
int num1 = int.Parse(results[0]);
string string1 = results[1];
You'd want to include some validation to ensure your first element is indeed a number (use int.TryParse), and that there are indeed two elements returned after you split the string.
I am trying to use regex to split the string into 2 arrays to turn out like this.
String str1 = "First Second [insideFirst] Third Forth [insideSecond] Fifth";
How do I split str1 to break off into 2 arrays that look like this:
ary1 = ['First Second','Third Forth','Fifth'];
ary2 = ['insideFirst','insideSecond'];
here is my solution
string str = "First Second [insideFirst] Third Forth [insideSecond] Fifth";
MatchCollection matches = Regex.Matches(str,#"\[.*?\]");
string[] arr = matches.Cast<Match>()
.Select(m => m.Groups[0].Value.Trim(new char[]{'[',']'}))
.ToArray();
foreach (string s in arr)
{
Console.WriteLine(s);
}
string[] arr1 = Regex.Split(str,#"\[.*?\]")
.Select(x => x.Trim())
.ToArray();
foreach (string s in arr1)
{
Console.WriteLine(s);
}
Output
insideFirst
insideSecond
First Second
Third Forth
Fifth
Plz Try below code. Its working fine for me.
String str1 = "First Second [insideFirst] Third Forth [insideSecond] Fifth";
var output = String.Join(";", Regex.Matches(str1, #"\[(.+?)\]")
.Cast<Match>()
.Select(m => m.Groups[1].Value));
string[] strInsideBreacket = output.Split(';');
for (int i = 0; i < strInsideBreacket.Count(); i++)
{
str1 = str1.Replace("[", ";");
str1 = str1.Replace("]", "");
str1 = str1.Replace(strInsideBreacket[i], "");
}
string[] strRemaining = str1.Split(';');
Plz look at below screen shot of output while debugging code:
Here,
strInsideBreacket is array of breacket value like insideFirst andinsideSecond
and strRemaining is array of First Second,Third Forth and Fifth
Thanks
Try this solution,
String str1 = "First Second [insideFirst] Third Forth [insideSecond] Fifth";
var allWords = str1.Split(new char[] { '[', ']' }, StringSplitOptions.RemoveEmptyEntries);
var result = allWords.GroupBy(x => x.Contains("inside")).ToArray();
The idea is that, first get all words and then the group it.
It seems to me that "user2828970" asked a question with an example, not with literal text he wanted to parse. In my mind, he could very well have asked this question:
I am trying to use regex to split a string like so.
var exampleSentence = "I had 185 birds but 20 of them flew away";
var regexSplit = Regex.Split(exampleSentence, #"\d+");
The result of regexSplit is: I had, birds but, of them flew away.
However, I also want to know the value which resulted in the second string splitting away from its preceding text, and the value which resulted in the third string splitting away from its preceding text. i.e.: I want to know about 185 and 20.
The string could be anything, and the pattern to split by could be anything. The answer should not have hard-coded values.
Well, this simple function will perform that task. The code can be optimized to compile the regex, or re-organized to return multiple collections or different objects. But this is (nearly) the way I use it in production code.
public static List<Tuple<string, string>> RegexSplitDetail(this string text, string pattern)
{
var splitAreas = new List<Tuple<string, string>>();
var regexResult = Regex.Matches(text, pattern);
var regexSplit = Regex.Split(text, pattern);
for (var i = 0; i < regexSplit.Length; i++)
splitAreas.Add(new Tuple<string, string>(i == 0 ? null : regexResult[i - 1].Value, regexSplit[i]));
return splitAreas;
}
...
var result = exampleSentence.RegexSplitDetail(#"\d+");
This would return a single collection which looks like this:
{ null, "I had "}, // First value, had no value splitting it from a predecessor
{"185", " birds but "}, // Second value, split from the preceding string by "185"
{ "20", " of them flew away"} // Third value, split from the preceding string by "20"
Being that this is a .NET Question and, apart from my more favoured approach in my other answer, you can also capture the Split Value another VERY Simple way. You just then need to create a function to utilize the results as you see fit.
var exampleSentence = "I had 185 birds but 20 of them flew away";
var regexSplit = Regex.Split(exampleSentence, #"(\d+)");
The result of regexSplit is: I had, 185, birds but, 20, of them flew away. As you can see, the split values exist within the split results.
Note the subtle difference compared to my other answer. In this regex split, I used a Capture Group around the entire pattern (\d+) You can't do that!!!?.. can you?
Using a Capture Group in a Split will force all capture groups of the Split Value between the Split Result Capture Groups. This can get messy, so I don't suggest doing it. It also forces somebody using your function(s) to know that they have to wrap their regexes in a capture group.