C# adding space after few characters in string

I wanna add s开发者_StackOverflowpace in string( string from array) after 2 characters, for example: 1234567890 should be 12 34 56 78 90, any suggestions how to do that?

---

"0123567236359783590203582835"
.ToCharArray()
.Aggregate("",
(result, c) => result += ((!string.IsNullOrEmpty(result) && (result.Length+1) % 3 == 0)
                          ? " " : "")
                         + c.ToString()
            );

// --> 01 23 56 72 36 35 97 83 59 02 03 58 28 35

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You would probably have to do a loop as such:

int i = 0;
int amount = 2;
string s = "1234567890";
string withspaces = "";

while (i+amount < s.Length) {
  s += s.Substring(i,i+amount);
  s += " ";
  i = i + amount;
}

This could be heavy on string usage, so make sure you read up on effective string concatenation

---

I would recommend following steps

1. Create a For loop which will go through the length of input string.

2. During each run of For loop concat ith elemen of string in to the result i.e.

   result+=input[i];

3. Inside for loop keep track of count and after every count%2 == 0 concat space to the result.

   result+=" ";

Hope this helps.

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If your looking specifically to format a fixed amount of numbers, such as the example above, the following will fit your needs.

int n = 1234567890;
string s = String.Format("{0:00 00 00 00 00}", n);

Note, this assumes that your 1234567890 is stored as a number. It will not format if n is of type string. You can overcome this by casting n to a number prior to formatting.

If you have an unbounded number of characters, you'll need a more versitile solution.