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How to assign a variable with .ConvertToString() method in C# to parse the message?

I am looking to learn how to assign a name to the newly converted string and then parse that string based on
string[] separatingStrings = { ",", "<<", ">>" };
string[] messages = message.Split(separatingStrings);
Console.WriteLine($"{messages.Length} substrings in text:");
below contains the var message converted to a string.
What is the name of the string so I can parse it and output it into unity debug.log?
private void ReceiveMessageLoop()
{
while (true)
{
var message = new NetMQMessage();
if (!_socket.TryReceiveMultipartMessage(MessageCheckRate, ref message, 2)) continue;
_messageSubject.OnNext(message);
Console.WriteLine($"0:{message[0].ConvertToString()} 1:{message[1].ConvertToString()}");
//Console.WriteLine(message);
}
}

You can't declare a variable in a string interpolation expression.
Console.WriteLine($"{string bar = "hello"}"); // This gives error CS1525: Invalid expression term 'string'
So instead, declare it outside the string interpolation, and you can assign it in the interpolation expression with an assignment expression.
string bar;
Console.WriteLine($"{bar = "hello"}"); // This is OK
Console.WriteLine(bar);
Your specific example:
string msg0, msg1;
Console.WriteLine($"0:{msg0 = message[0].ConvertToString()} 1:{msg1 = message[1].ConvertToString()}");
Console.WriteLine(msg0);
Console.WriteLine(msg1);
Bonus tip: You can, however, use an out variable declaration in an interpolation expression. The scope is the same as the line (not somehow local to the interpolation expression). e.g.:
class Program
{
static string Test(out string x, string y) {
return x = y;
}
static void Main(string[] args)
{
Console.WriteLine($"{Test(out string bar, "Hello")}");
Console.WriteLine(bar);
}
}

C# Search filters- ignore specific diacritics

I'm writing a program, and I'm using a LINQ search to a SQL Server database (although this is probably subject to change at some point). I want to make filters for certain diacritics, e.g search for tilde ẽ but not circumflex ê. I've seen examples of how to ignore all, but none saying how to ignore specific ones. Will I just have to convert all strings searched manually by iterating through the strings and changing them?

If your database collation permits it, you have to write a method to ignore specific characters.
If you want to ignore ALL diacrits you have to define your own method like :
public static string RemoveDiacritics(this String s)
{
String normalizedString = s.Normalize(NormalizationForm.FormD);
StringBuilder stringBuilder = new StringBuilder();
for (int i = 0; i < normalizedString.Length; i++)
{
Char c = normalizedString[i];
if (System.Globalization.CharUnicodeInfo.GetUnicodeCategory(c) != System.Globalization.UnicodeCategory.NonSpacingMark)
stringBuilder.Append(c);
}
return stringBuilder.ToString();
}
EDIT:
public static class StringExtensions
{
public static bool CaseContains(this string baseStr, string textToSearch, StringComparison compareMode)
{
return (baseStr.IndexOf(textToSearch, compareMode) != -1);
}
}
and call it with
if(text.CaseContains(whattextisearch, StringComparison.CurrentCulture))
.....

c# if contains AND/OR

Is there a variant of this?
if (blabla.Contains("I'm a noob") | blabla.Contains("sry") | blabla.Contains("I'm a noob "+"sry"))
{
//stuff
}
like:
if (blabla.Contains("I'm a noob) and/or ("sry")
{
//stuff
}
Help is appreciated!

You can't collapse it quite as far as you asked, but you can do:
if (blabla.Contains("I'm a noob") || blabla.Contains("sry"))
{
//stuff
}
The "and" case is handled here because a string with both would actually pass both of the statements in the "Or".

As far as I'm aware, there are no built-in methods to do this. But with a little LINQ and extension methods, you can create your own methods that will check to see if a string contains any or all tokens:
public static class ExtensionMethods{
public static bool ContainsAny(this string s, params string[] tokens){
return tokens.Any(t => s.Contains(t));
}
public static bool ContainsAll(this string s, params string[] tokens){
return tokens.All(t => s.Contains(t));
}
}
You could use it like this (remember, params arrays take a variable number of parameters, so you're not limited to just two like in my example):
var str = "this is a string";
Console.WriteLine(str.ContainsAny("this", "fake"));
Console.WriteLine(str.ContainsAny("doesn't", "exist"));
Console.WriteLine(str.ContainsAll("this", "is"));
Console.WriteLine(str.ContainsAll("this", "fake"));
Output:
True
False
True
False
Edit:
For the record, LINQ is not necessary. You could just as easily write them this way:
public static class ExtensionMethods{
public static bool ContainsAny(this string s, params string[] tokens){
foreach(string token in tokens)
if(s.Contains(token)) return true;
return false;
}
public static bool ContainsAll(this string s, params string[] tokens){
foreach(string token in tokens)
if(!s.Contains(token)) return false;
return true;
}
}

var arr = new[]{"I'm a noob" ,"sry", "I'm a noob +sry"};
if(arr.Any(x => blabla.Contains(x)))
{
}

You can use a regex:
Regex r = new Regex("I'm a noob|sry|I'm a noob sry");
if(r.IsMatch(blabla)) {
//TODO: do something
}
Regular expressions have other advanced features like: a* matches with the empty string, a, aa, aaa,...
The funny part is that if you "compile" the regex (for instance using new Regex("I'm a noob|sry|I'm a noob sry",RegexOptions.Compiled), C# will turn it automatically into the fastest solution mechanism possible. For instance if blabla is a 100k chars string, you will only run once over the entire string. And for instance redundant parts like I'm a noob sry will be omitted automatically.

IEnumerable<string> function c# .net

i have faced this question in interview as below?
let us consider the string named
string gowtham="test1,test2,test3" ;
i need to convert in to IEnumerable string function
i need a output to be as
new[] {"test1", "test2","test3" }
what i did is i have created a string() function by spliting values by comma seperated as below
string[] mysamples= gowtham.Split(',');
i do not know how to proceed after
waiting for your responses?

Every array is already a IEnumerable, in your case if you want to explicit cast to one IEnumerable of string you could use
IEnumerable<string> mysamplesEnumerable = mysamples as IEnumerable<string>
if you interviewer wanted a function that did this you could do
IEnumerable<string> SplitEnumByComa(string input)
{
return input.Split(',');
}

If I understand your question clearly, you can use a method like this;
public static IEnumerable<string> YourMethod()
{
string gowtham = "test1,test2,test3";
string[] mysamples = gowtham.Split(',');
List<string> senum = new List<string>();
foreach ( string s in mysamples )
{
senum.Add(s);
}
return senum as IEnumerable<string>;
}
Since string[] implements IEnumerable<T> interface, it seems you just need to cast it as IEnumerable<T>
EDIT: Since Magnus and LukeH warned me, there is an easy way also what you want to do.
public static IEnumerable<string> YourMethod()
{
string gowtham = "test1,test2,test3";
return gowtham .Split(',');
}

Parsing formatted string

I am trying to create a generic formatter/parser combination.
Example scenario:
I have a string for string.Format(), e.g. var format = "{0}-{1}"
I have an array of object (string) for the input, e.g. var arr = new[] { "asdf", "qwer" }
I am formatting the array using the format string, e.g. var res = string.Format(format, arr)
What I am trying to do is to revert back the formatted string back into the array of object (string). Something like (pseudo code):
var arr2 = string.Unformat(format, res)
// when: res = "asdf-qwer"
// arr2 should be equal to arr
Anyone have experience doing something like this? I'm thinking about using regular expressions (modify the original format string, and then pass it to Regex.Matches to get the array) and run it for each placeholder in the format string. Is this feasible or is there any other more efficient solution?

While the comments about lost information are valid, sometimes you just want to get the string values of of a string with known formatting.
One method is this blog post written by a friend of mine. He implemented an extension method called string[] ParseExact(), akin to DateTime.ParseExact(). Data is returned as an array of strings, but if you can live with that, it is terribly handy.
public static class StringExtensions
{
public static string[] ParseExact(
this string data,
string format)
{
return ParseExact(data, format, false);
}
public static string[] ParseExact(
this string data,
string format,
bool ignoreCase)
{
string[] values;
if (TryParseExact(data, format, out values, ignoreCase))
return values;
else
throw new ArgumentException("Format not compatible with value.");
}
public static bool TryExtract(
this string data,
string format,
out string[] values)
{
return TryParseExact(data, format, out values, false);
}
public static bool TryParseExact(
this string data,
string format,
out string[] values,
bool ignoreCase)
{
int tokenCount = 0;
format = Regex.Escape(format).Replace("\\{", "{");
for (tokenCount = 0; ; tokenCount++)
{
string token = string.Format("{{{0}}}", tokenCount);
if (!format.Contains(token)) break;
format = format.Replace(token,
string.Format("(?'group{0}'.*)", tokenCount));
}
RegexOptions options =
ignoreCase ? RegexOptions.IgnoreCase : RegexOptions.None;
Match match = new Regex(format, options).Match(data);
if (tokenCount != (match.Groups.Count - 1))
{
values = new string[] { };
return false;
}
else
{
values = new string[tokenCount];
for (int index = 0; index < tokenCount; index++)
values[index] =
match.Groups[string.Format("group{0}", index)].Value;
return true;
}
}
}

You can't unformat because information is lost. String.Format is a "destructive" algorithm, which means you can't (always) go back.
Create a new class inheriting from string, where you add a member that keeps track of the "{0}-{1}" and the { "asdf", "qwer" }, override ToString(), and modify a little your code.
If it becomes too tricky, just create the same class, but not inheriting from string and modify a little more your code.
IMO, that's the best way to do this.

It's simply not possible in the generic case. Some information will be "lost" (string boundaries) in the Format method. Assume:
String.Format("{0}-{1}", "hello-world", "stack-overflow");
How would you "Unformat" it?

Assuming "-" is not in the original strings, can you not just use Split?
var arr2 = formattedString.Split('-');
Note that this only applies to the presented example with an assumption. Any reverse algorithm is dependent on the kind of formatting employed; an inverse operation may not even be possible, as noted by the other answers.

A simple solution might be to
replace all format tokens with (.*)
escape all other special charaters in format
make the regex match non-greedy
This would resolve the ambiguities to the shortest possible match.
(I'm not good at RegEx, so please correct me, folks :))

After formatting, you can put the resulting string and the array of objects into a dictionary with the string as key:
Dictionary<string,string []> unFormatLookup = new Dictionary<string,string []>
...
var arr = new string [] {"asdf", "qwer" };
var res = string.Format(format, arr);
unFormatLookup.Add(res,arr);
and in Unformat method, you can simply pass a string and look up that string and return the array used:
string [] Unformat(string res)
{
string [] arr;
unFormatLoopup.TryGetValue(res,out arr); //you can also check the return value of TryGetValue and throw an exception if the input string is not in.
return arr;
}