Remove element from comma separeted string and return new a comma separated string

Question

I am trying to remove a element from a comma separated string.

Input : "monkey,bear,cobra";
remove bear
Output : "monkey, cobra";

if i do this step by step, it works
string[] AnimalArray = AnimalString.Split(','); //split
List<string> AnimalList = AnimalArray.ToList();//list
AnimalList.Remove("bear");//remove element
Console.WriteLine(String.Join(",", AnimalList.ToArray())); //recreate the comma-seperated string

if I do this all on one line, I get this error
'bool' does not contain a definition for 'ToArray'

string AnimalString2 = "monkey,bear,cobra";
Console.WriteLine(String.Join(",", AnimalString2.Split(',').ToList().Remove("bear").ToArray()));

Where is the bool in this action ?
What is the best way to do this ?

https://code.sololearn.com/c7D1LIM26Tc3

Answer 1

The problem is in the ".ToArray()" call after the "Remove("bear")" call. The List class indeed has a remove method, which removes the element from the list. However, that remove method does not return a reference to the list itself; it returns a boolean value based on whether or not it succeeds in finding the specified value.

You can see this if you call:

Console.WriteLine(AnimalString2.Split(',').ToList().Remove("bear"));
//output: "True"

In other words, you can't cotinue to chain method-calls after the .Remove() call, since it does not return a reference to the underlying List object.

Unfortunately, the call to Remove() has to be done on a separate line. The only way to get around this would be to write your own Remove function, which returns a reference to the List.

This is why the error message is telling you "'bool' does not contain a definition for 'ToArray'". It's interpreting the code as:

True.toArray()

Which makes no sense to the compiler.

Answer 2

Jack McCarthy nailed it and here's what you can do with LINQ if you wish to exclude 🐻 from the list in one-line:-

string.Join(
", ",
AnimalString.Split(',')
.Where(
animal =>
animal != "bear")
);

Answer 3

Thanks. Clear explanation.

Answer 4

Use a datastructure to operate performant on data sets. String is data and therefore imperformant for your purpose/algorithm.

Answer 5

Daniel Adam Can you explain yourself more ?
This is not a dataset or a database.
It is a string in a protocol and the result should be a string a well. Why should i use dataset in such a small method ?