Encoding a string into utf-8 type

Chinmay Joshi

6y1kLearn iOS Programming

How can I convert an Emoji in a string to an equivalent utf-8 code ?

eg: "Hi this is Chinmay ! ☺ "

6 Replies

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Chinmay Joshi6y ago
Getting the below exception

Unhandled Exception: System.ArgumentOutOfRangeException: startIndex cannot be larger than length of string.
Parameter name: startIndex
at System.String.Substring(Int32 startIndex, Int32 length)
at ConsoleApp3.Program.ConvertEmoji2UnicodeHex(String emoji) in C:\Users\chinm\source\repos\ConsoleApp3\ConsoleApp3\Program.cs:line 25
at ConsoleApp3.Program.Main(String[] args) in C:\Users\chinm\source\repos\ConsoleApp3\ConsoleApp3\Program.cs:line 43
+2
Chandresh Pansuriya6y ago
1. public static string ConvertEmoji2UnicodeHex(string emoji)
2. {
3. if (string.IsNullOrWhiteSpace(emoji))
4. return emoji;
6. byte[] bytes = Encoding.UTF8.GetBytes(emoji);
7. string firstItem = Convert.ToString(bytes[0], 2);
9. int iv;
10. if (bytes.Length == 1)
11. {
12. iv = Convert.ToInt32(firstItem, 2);
13. }
14. else
15. {
16. StringBuilder sbBinary = new StringBuilder();
17. sbBinary.Append(firstItem.Substring(bytes.Length + 1).TrimStart('0'));
18. for (int i = 1; i < bytes.Length; i++)
19. {
20. string item = Convert.ToString(bytes[i], 2);
21. item = item.Substring(2);
22. sbBinary.Append(item);
23. }
25. iv = Convert.ToInt32(sbBinary.ToString(), 2);
26. }
28. return Convert.ToString(iv, 16).PadLeft(4, '0');
29. }
+2

Laxmidhar Sahoo6y ago

using System.Text;
static void Main()
{
string unicodeString = "This string contains the unicode character Pi (\u03a0)";
// Create two different encodings.
Encoding ascii = Encoding.ASCII;
Encoding unicode = Encoding.Unicode;
// Convert the string into a byte array.
byte[] unicodeBytes = unicode.GetBytes(unicodeString);
// Perform the conversion from one encoding to the other.
byte[] asciiBytes = Encoding.Convert(unicode, ascii, unicodeBytes);
// Convert the new byte[] into a char[] and then into a string.
char[] asciiChars = new char[ascii.GetCharCount(asciiBytes, 0, asciiBytes.Length)];
ascii.GetChars(asciiBytes, 0, asciiBytes.Length, asciiChars, 0);
string asciiString = new string(asciiChars);
// Display the strings created before and after the conversion.
Console.WriteLine("Original string: {0}", unicodeString);
Console.WriteLine("Ascii converted string: {0}", asciiString);
}
For more details
https://docs.microsoft.com/en-us/dotnet/api/system.text.encoding?view=netcore-3.1

Jignesh Kumar6y ago

Hi Chinmay,

Please find below url which will help you,

https://stackoverflow.com/questions/44728740/how-to-convert-emoticons-to-its-utf-32-escaped-unicode

Aman Gupta6y ago

Hi chinmay, you can refer this public static string ConvertEmoji2UnicodeHex(string emoji){if (string.IsNullOrWhiteSpace(emoji))return emoji;byte[] bytes = Encoding.UTF8.GetBytes(emoji);string firstItem = Convert.ToString(bytes[0], 2); int iv;if (bytes.Length == 1){iv = Convert.ToInt32(firstItem, 2);}else{StringBuilder sbBinary = new StringBuilder();sbBinary.Append(firstItem.Substring(bytes.Length + 1).TrimStart('0'));for (int i = 1; i < bytes.Length; i++){string item = Convert.ToString(bytes[i], 2);item = item.Substring(2);sbBinary.Append(item);}iv = Convert.ToInt32(sbBinary.ToString(), 2);}return Convert.ToString(iv, 16).PadLeft(4, '0');}

Aman Gupta6y ago

Or You can use this public static string ConvertEmoji2UnicodeHex(string emoji){if (string.IsNullOrWhiteSpace(emoji))return emoji;byte[] bytes = Encoding.UTF8.GetBytes(emoji);string firstItem = Convert.ToString(bytes[0], 2); int iv;if (bytes.Length == 1){iv = Convert.ToInt32(firstItem, 2);}else{StringBuilder sbBinary = new StringBuilder();sbBinary.Append(firstItem.Substring(bytes.Length + 1).TrimStart('0'));for (int i = 1; i < bytes.Length; i++){string item = Convert.ToString(bytes[i], 2);item = item.Substring(2);sbBinary.Append(item);}iv = Convert.ToInt32(sbBinary.ToString(), 2);}return Convert.ToString(iv, 16).PadLeft(4, '0');}