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Is there a Difference between Splitting on Character to Splitting on Phrase

Is there any difference in the output of these two functions? I have a text editor I'm modifying on a website. The editor currently splits by character but I am switching it to split by a word or phrase.
Split by Character
string words = "word1*word2*word3*word4";
string[] collectionofWords = words.Split('*');
Split by Word
string words = "word1***word2***word3***word4";
string[] collectionofWords = words.Split(new string[] { "***" }, StringSplitOptions.None);
Do these functions work exactly the same even in difficult scenarios?
In my example above they appear to word identically but what if there was empty data (EG1) or what if there was characters at the beginning or end of the string (EG2) would these functions still produce identical results?
Is there any scenario where these two functions would produce different results given the same data being passed in?
EG1
string words = "word1*word2**word4";
string words = "word1***word2******word4";
EG2
string words = "*word1*word2*word3*word4*";
string words = "***word1***word2***word3***word4***";

If you are afraid of different results you can use another method splitting on a regex match:
string words = "word1*word2*word3*word4";
string words2 = "word1***word2***word3***word4";
string[] arr = Regex.Split(words, #"\*+");
string[] arr2 = Regex.Split(words2, #"\*+");
if (arr.SequenceEqual(arr2))
Console.WriteLine("Arrays are equal");

In contrary to what suggested here, and from string class implementation, those are two different methods, with different dependencies.
By design the expected output should be the same from MSDN documentation (putting aside the performance differences).

In short: no. There is no functional difference between splitting using the character overload and splitting using a string overload. However splitting with a string should be slightly less efficient than due to more checks required.
Also as far as I know they would function identically under the same circumstances since they are basically the same code just with different comparisons.

C# Regex, extract strings by reference string

Edit: Solution by #Heinzi
https://stackoverflow.com/a/1731641/87698
I got two strings, for example someText-test-stringSomeMoreText? and some kind of pattern string like this one {0}test-string{1}?.
I'm trying to extract the substrings from the first string that match the position of the placeholders in the second string.
The resulting substrings should be: someText- and SomeMoreText.
I tried to extract with Regex.Split("someText-test-stringSomeMoreText?", "[.]*test-string[.]*\?". However this doesn't work.
I hope somebody has another idea...

One option you have is to use named groups:
(?<prefix>.*)test-string(?<suffix>.*)\?
This will return 2 groups containing the wanted prefix and the suffix.
var match = Regex.Match("someText-test-stringSomeMoreText?",
#"(?<prefix>.*)test-string(?<suffix>.*)\?");
Console.WriteLine(match.Groups["prefix"]);
Console.WriteLine(match.Groups["suffix"]);

I got a solution, at least its a bit dynamical.
First I split up the pattern string {0}test-string{1}? with
string[] patternElements = Regex.Split(inputPattern, #"(\\\{[a-zA-Z0-9]*\})");
Then I spit up the input string someText-test-stringSomeMoreText? with
string[] inputElements = inputString.Split(patternElements, StringSplitOptions.RemoveEmptyEntries);
Now the inputElements are the text pieces corresponding to the placeholders {0},{1},...

Spliting string into 3 parts

I'm trying to learn to split strings. I have a string, for example, Adams, John - 22.6.2001. What is the easiest way to split each of the following pieces of information into particular strings? I need the name, surname, and date.
This is the solution that I tried myself:
string st = "Adams, John - 22.6.2001"
st = st.Trim(); // To replace all possible white spaces? But I don't know how can I cut each of details into string.

what is the easiest way to trim each of these information into
particular strings: name, surname, date ?
Looks like you want to split sting based on , and space.
string[] splitArray = st.Split(new string[] { ",", " "}, StringSplitOptions.RemoveEmptyEntries);
EDIT:
As far as parsing names is concerned, you have to define some kind of rules that how your string would have names. For example your string could have multiple names, First, Last, Middle separated by commas, in that case the above statement will not give you the result that you need. You have to define some rules to make your input string consistent, and based on that you can use string.Split to get values.

You can do it using String.Split() to break the parts of the string into a string array. Trim() is used to remove white-space from the start and end of a string, so this can be used to tidy up the resulting strings.
string st = "Adams, John - 22.6.2001";
// first split on dash, to seperate name and date
string[] partsArray = st.Split('-');
// now split first part to get first and surname (trim surrounding whitespace)
string[] nameArray = partsArray[0].Split(',');
string firstName = nameArray[1].Trim();
string lastName = nameArray[0].Trim();
// get date from other part (again trim whitespace)
string dateAsString = partsArray[1].Trim();
Parsing text is a complex topic, but I think the question was just looking for an introduction. There are many edge cases and issues which you'd need to add to a parser to get close to 100% results for different name and date formats. If you were importing data like this in bulk, you would use a CSV file or similar to break up the parts before importing.

Use String.Split method and use separator as ,

Split String using delimiter that exists in the string

I have a problem and I am wondering if there is any smart workaround.
I need to pass a string through a socket to a web application. This string has three parts and I use the '|' as a delimiter to split at the receiving application into the three separate parts.
The problem is that the '|' character can be a character in any of the 3 separate strings and when this occurs the whole splitting action distorts the strings.
My question therefore is this:
Is there a way to use a char/string as a delimiter in some text while this char/string itself might be in the text?

The general pattern is to escape the delimiter character. E.g. when '|' is the delimiter, you could use "||" whenever you need the character itself inside a string (might be difficult if you allow empty strings) or you could use something like '\' as the escape character so that '|' becomes "\|" and "\" itself would be "\\"

The matter here is that given the following string:
string toParse = "What|do you|want|to|say|?";
It can be parsed in many several ways:
"What
do you
want|to|say|?"
or
"What|do you
want
to|say|?"
and so on...
You can define rules to parse your string, but coding it will be hard, and it will seem counter intuitive to the final user.
The string must contains an escape character that indicates that the symbol "|" is wanted, not the separator.
This could be for example "\|".
Here a full example using regex:
using System.Text.RegularExpressions;
//... Put this in the main method of a Console Application for instance.
// The '#' character before the strings are to specify "raw" strings, where escape characters '\' are not escaped
Regex reg = new Regex(#"^((?<string1>([^\|]|\\\|)+)\|)((?<string2>([^\|]|\\\|)+)\|)(?<string3>([^\|]|\\\|)+)$");
string toTest = #"user\|dureuill|deserves|an\|upvote";
MatchCollection matches = reg.Matches(toTest);
if (matches.Count != 1)
{
throw new FormatException("Bad formatted pattern.");
}
Match match = matches[0];
string string1 = match.Groups["string1"].Value.Replace(#"\|", "|");
string string2 = match.Groups["string2"].Value.Replace(#"\|", "|");
string string3 = match.Groups["string3"].Value.Replace(#"\|", "|");
Console.WriteLine(string1);
Console.WriteLine(string2);
Console.WriteLine(string3);
Console.ReadKey();

Is there a way to use a char/string as a delimiter in some text while
this char/string itself might be in the text?
Simple answer: No.
This is of course when the string/delimiter is exactly the same, without doing modifications to the text.
There are of course possible workarounds. One possible solution is that you might want to have a minimum/fixed width between delimiters, this is not perfect however.
Another possible solution is to select a delimiter (sequence of characters) that will never occur together in your text. This requires you to change the source and consumer.
When I need to use delimiters I normally select a delimiter that I am 99.9% sure will never occur in normal text, the delimiter may vary depending on what kind of text that I expect.
Here's a quote from Wikipedia:
Because delimiter collision is a very common problem, various methods
for avoiding it have been invented. Some authors may attempt to avoid
the problem by choosing a delimiter character (or sequence of
characters) that is not likely to appear in the data stream itself.
This ad-hoc approach may be suitable, but it necessarily depends on a
correct guess of what will appear in the data stream, and offers no
security against malicious collisions. Other, more formal conventions
are therefore applied as well.
Just a side note to your use-case, why not use a protocol for the data that is sent? Such as protobuf?

Maybe it is useful to HTMLEncode and HTMLDecode your strings first and then attach them together with your delimiter.

I think you either
1)Find a character or set of characters together that would never appear in the string
or
2)Use fixed length strings and pad.

Maybe adapt the delimeter if you have the flexibility to do this? So instead of String1|String2 the string could read "String1"|"String2".
If pipes are unwanted - put some simple validation in place during creation/entry of this string?

Instead of using | as delimiter, you could find a delimiter that's not present in the message parts and pass it along at the beginning of the sent message. Here's an example using an integer as delimiter:
String[] parts = {"this is a message", "it's got three parts", "this one's the last"};
String delimiter = null;
for (int i = 0; i < 100; i++) {
String s = Integer.toString(i);
if (parts[0].contains(s) || parts[1].contains(s) || parts[2].contains(s))
continue;
delimiter = s;
break;
}
String message = delimiter + "#" + parts[0] + delimiter + parts[1] + delimiter + parts[2];
Now the message is 0#this is a message0it's got three parts0this one's the last.
On the receiving end you start by finding the delimiter and split the message string on that:
String[] tmp = message.split("#", 2);
String[] parts = tmp[1].split(tmp[0]);
It's not the most efficient possible solution, since it requires scanning the message parts several times, but it's very easy to implement. If you don't find a value for delimiter and null happens to be part of the message, you might experience unexpected results.

Comparing strings with quotation marks

Hello guys i'm trying to create a program in C# where I am comparing two strings in which within the strings they have the double quotation marks. My problem is how do I compare them for equality because it seems the compiler ignores the words within the quotation marks and does not give me the right comparison.
An example is if
string1 = Hi "insert name" here.
string2 = Hi "insert name" here.
I want to use string1.equals(string2). But it seems it tells me the strings are not equal. How do I do this? Please help.
PS. I have no control on what the strings will look like as they are dynamic variables. So I can't just say add an escape sequence to it.

string s1 = "Hi \"insert name\" here.";
string s2 = "Hi \"insert name\" here.";
Console.WriteLine((s1 == s2).ToString()); //True
I have no problem ...

.NET will not ignore string values with double quotes when doing comparisons. I think your analysis of what is happening is flawed. For example, given these values:
var string1 = "This contains a \"quoted value\"";
var string2 = "This contains a \"quoted value\"";
var string3 = "This contains a \"different value\"";
string1.Equals(string2) will equal true, and string2.Equals(string3) will equal false.
Here are some potential reasons why you're not seeing an expected result when comparing:
One string may contain different quote characters than another. For example, "this", and “this” are completely different strings.
Your comparison may be failing due to other content not matching. For example, one string may have trailing spaces, and the other may not.
You may be comparing two objects instead of two strings. Object.Equals compares whether two objects are the same object. If you're not dealing with String references, the wrong comparison may be happening.
There are many more potential causes for your issue, but it's not because string comparison ignores double quotes. The more details you provide in your question, the easier it is for us to narrow down what you're seeing.