使用“，”分割字符串并存储在数组列表中

Question

1. Here is the string in C# : string Id = "1LE, 1GE";
2. Split the string using comma .
3. Store it in ArrayList .

My code is not working on online compiler.

string Id = "1LE, 1GE";
ArrayList centerIds_list = new ArrayList();
centerIds_list.AddRange(centerIds);

I need the output as 2 elements with spilited string .

Answer 1

Well, string.Split returns array - string[] so if you are not going to add / remove items, just put

  string[] centerIds_list = Id.Split(',');

If you want to add/remove items into/from the collection (and that's why array is out of question), try List<string> instead of obsolete ArrayList :

   List<string> centerIds_list = new List<String>(Id.Split(','));

Finally, if you insist on ArrayList :

   ArrayList centerIds_list = new ArrayList(Id.Split(','));

Few more details:

"1LE, 1GE".Split(',') will return "1LE" , " 1GE" , please, note leading space . You can get rid of it either by splitting on ", " (not ',' ):

   Id.Split(new string[] { ", "}, StringSplitOptions.None);

Or with a help of Linq : .Select(item => item.Trim()) followed by materialization ( .ToArray() or .ToList() ), eg

   string[] centerIds_list = Id
     .Split(',')
     .Select(item => item.Trim())
     .ToArray();

Or

   List<string> centerIds_list = centerIds_list = Id
     .Split(',')
     .Select(item => item.Trim())
     .ToList();

Or

   ArrayList centerIds_list = new ArrayList(Id
     .Split(',')
     .Select(item => item.Trim())
     .ToArray());

Answer 2

You are missing line

var centerIds = Id.Split(',');

You need to split string by comma and then create instance of ArrayList .

Try below code

string Id="1LE, 1GE";
var centerIds = Id.Split(','); //This was missing
ArrayList centerIds_list = new ArrayList();
centerIds_list.AddRange(centerIds);

As most of the comments raised this point, I want to include it as well.

Use List<string> instead of ArrayList .

List<string> centerIds_list = "1LE, 1GE".Split(',').ToList(); //One line solution

If you want to get rid of white spaces, then use Trim()

List<string> centerIds_list = "1LE, 1GE".Split(',').Select(x => x.Trim()).ToList();

Answer 3

These days nobody uses ArrayList , instead they use a strongly typed generic. In your case that would be List<string> .

To get the parts as a List<string> you can do:

Id.Split(',').ToList();

If you want to remove any spacing around the individual parts then you can do:

Id.Split(',').Select(s => s.Trim()).ToList();

Answer 4

string Ids="1LE, 1GE"; List centerIds_list = Ids.Split(',').Select(x => x.Trim()).ToList(); foreach (var item in centerIds_list) {

           Console.WriteLine(item);  

        }

Answer 5

I know this is not answering the question per se, but if performance is an issue, and you are working on a large about of data to split (eg a large csv file), then take a look at this article as it talks about using Span as an alternative to String.split.

[ https://ladeak.wordpress.com/2019/06/21/the-power-of-span/amp/?__twitter_impression=true]