How to convert a list of strings to a single string in Unity (C#)

Question

I'm new to C#, and apologies for the noob question - I'm trying to convert a list of strings to a single string so I can use it with WWWForm's POST function.

If I have a list of strings (e.g. kidIds = ["a#123", "b#123"]), how do I easily convert it to a single string ("a#123, b#123")? In Javascript, I would simply do kidIds.join(","), but I'm not sure how to do it in C#.

I tried doing kidIds.ToArray().ToString(), but it's not really giving me what I want. I could loop through the entire list using a for loop, but I was wondering if there's a simpler one liner I could use?

https://msdn.microsoft.com/en-us/library/57a79xd0(v=vs.110).aspx — apocalypse, Dec 29 '16 at 03:37

Mohit S · Answer 1 · 2016-12-29T04:40:03.267

Since you are new to C# I would like to tell you that, you were trying to convert a list of strings to a single string. No it is not a list of string but it is a array of string. List of strings would be initalize like

List<string> SomeName = new List<string>();

Where as your one is declared as array. Now you can Join the Array of strings into one string as same as Javascript like

string SomeString = String.Join(",", kidIds);

The string.Join method combines many strings into one. It receives two arguments: an array (or IEnumerable) and a separator string.

You can also create one string out of the String array using + that would concatenate the strings like

string smstr = String.Empty;
for(int i=0; i<kidIds.Length; i++)
{
    smstr = smstr + kidIds[i];
    //or
    smstr += kidIds[i]
}

You can also choose StringBuilder to create one string out of array of strings since StringBuilder.Append() method is much better than using the + operator like

StringBuilder sb = new StringBuilder();
for(int i=0;i<kidIds.Length;i++)
{
    sb.Append(kidIds[i]);
}

But StringBuilder is good when the concatenations are less than 1000, String.Join() is even more efficient than StringBuilder.

score 6 · Accepted Answer · answered Dec 29 '16 at 03:38

6

There is basically the same thing as JavaScript's join()

String.Join Method

answered Dec 29 '16 at 03:38

shole

4,046
2
29
69

Thank you, this worked perfectly! Will accept answer after the 5 mins have elapsed. – Dan Tang Dec 29 '16 at 03:44

score 4 · Answer 3 · answered Dec 29 '16 at 03:42

4

Use String.Join(',', kidIds);

https://msdn.microsoft.com/en-us/library/tk0xe5h0(v=vs.110).aspx

answered Dec 29 '16 at 03:42

Z .

12,657
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This should be the accepted answer! Thanks a lot, I knew there was a oneliner for that. Except I had to use `string.Join(",", kidIds)` since it expected a `string` not a `char` as first parameter. – derHugo Oct 23 '18 at 07:12

score 2 · Answer 4 · answered Dec 29 '16 at 03:42

2

Perhaps you can try the function concat, like

String str = "";

str = kidIds[0] + kidIds[1];

or

str = str.concat(kidIds[0], kidIds[0]);

or

for(int i=0;i<length;i++)
{
    str += kidIds[i];
}

I think i would help.

answered Dec 29 '16 at 03:42

Jeffrey Cheong

348
3
13

score 1 · Answer 5 · answered Dec 29 '16 at 04:50

You can do this using following code...

 string[] kidIds = { "a#123", "b#123" };

        String str = "";

        foreach (var kidId in kidIds)
        {
            str += kidId + ",";
        }

        str = str.Remove(str.Length - 1,1); // this line use for remove last comma

thanks...

How to convert a list of strings to a single string in Unity (C#)

5 Answers5