string[0] get first character from string [duplicate]

Question

I have a problem which I do not understand. Here is my code:

String input = "3 days ago" String firstCharacter = input[0].ToString(); //Returns 3 int firstCharacter = (int)input[0]; //Returns 51

Why does it return 51?

More information:

In case that input = "5 days ago", then int firstCharacter is 53.

Because the 3 is a char with 51 code. You cast a char to an int. Check asciitable.com — Wiktor Stribiżew
– Wiktor Stribiżew, Commented Oct 12, 2016 at 15:33
What are you trying to achieve? This is normal behavior in .NET. You can cast a char to int and int to char. — Alex
– Alex, Commented Oct 12, 2016 at 15:39

duncan · Accepted Answer · 2016-10-12 15:40:06Z

Casting a char to int in this way will give you its ASCII value which for 3 is equal to 51. You can find a full list here:

You want to do something like this instead:

Char.GetNumericValue(input[0]);

Innat3 · Accepted Answer · 2016-10-12 15:50:13Z

You can also use substring to extract it as a string instead of a char and avoid having to cast it:

 string input = "3 days ago"; string sFirstCharacter = input.Substring(0, 1); int nFirstCharacter = int.Parse(input.Substring(0, 1));

2 Answers 2