ASCII table. This is a quick reference for ASCII character codes. We use a simple C# program to generate this dynamically. We see the ASCII character codes for the first 128 characters.
Code sample. Please notice the C# console program that generates this table. A way to convert chars and ints is found in the code.
Table. Here are the first 128 characters. Some of the characters are escaped on the ASCII column. Many of the characters are control characters, which are not widely used.
Decimal ASCII Hex
0 control 00
1 control 01
2 control 02
3 control 03
4 control 04
5 control 05
6 control 06
7 control 07
8 control 08
9 \t 09
10 \n 0A
11 \v 0B
12 \f 0C
13 \r 0D
14 control 0E
15 control 0F
16 control 10
17 control 11
18 control 12
19 control 13
20 control 14
21 control 15
22 control 16
23 control 17
24 control 18
25 control 19
26 control 1A
27 control 1B
28 control 1C
29 control 1D
30 control 1E
31 control 1F
32 space 20
33 ! 21
34 " 22
35 # 23
36 $ 24
37 % 25
38 & 26
39 ' 27
40 ( 28
41 ) 29
42 * 2A
43 + 2B
44 , 2C
45 - 2D
46 . 2E
47 / 2F
48 0 30
49 1 31
50 2 32
51 3 33
52 4 34
53 5 35
54 6 36
55 7 37
56 8 38
57 9 39
58 : 3A
59 ; 3B
60 < 3C
61 = 3D
62 > 3E
63 ? 3F
64 @ 40
65 A 41
66 B 42
67 C 43
68 D 44
69 E 45
70 F 46
71 G 47
72 H 48
73 I 49
74 J 4A
75 K 4B
76 L 4C
77 M 4D
78 N 4E
79 O 4F
80 P 50
81 Q 51
82 R 52
83 S 53
84 T 54
85 U 55
86 V 56
87 W 57
88 X 58
89 Y 59
90 Z 5A
91 [ 5B
92 \ 5C
93 ] 5D
94 ^ 5E
95 _ 5F
96 ` 60
97 a 61
98 b 62
99 c 63
100 d 64
101 e 65
102 f 66
103 g 67
104 h 68
105 i 69
106 j 6A
107 k 6B
108 l 6C
109 m 6D
110 n 6E
111 o 6F
112 p 70
113 q 71
114 r 72
115 s 73
116 t 74
117 u 75
118 v 76
119 w 77
120 x 78
121 y 79
122 z 7A
123 { 7B
124 | 7C
125 } 7D
126 ~ 7E
127 control 7F
Console program. This program uses the PadRight method to pad each column so it appears correctly. It uses a simple for-loop construct to loop through all the ASCII characters.
using System;
class Program
{
static void Main()
{
Console.Write("Decimal".PadRight(10));
Console.Write("ASCII".PadRight(10));
Console.Write("Hex".PadRight(10));
Console.WriteLine();
int min = 0;
int max = 128;
for (int i = min; i < max; i++)
{
// Get ASCII character.
char c = (char)i;
// Get display string.
string display = string.Empty;
if (char.IsWhiteSpace(c))
{
display = c.ToString();
switch (c)
{
case '\t':
display = "\\t";
break;
case ' ':
display = "space";
break;
case '\n':
display = "\\n";
break;
case '\r':
display = "\\r";
break;
case '\v':
display = "\\v";
break;
case '\f':
display = "\\f";
break;
}
}
else if (char.IsControl(c))
{
display = "control";
}
else
{
display = c.ToString();
}
// Write table row.
Console.Write(i.ToString().PadRight(10));
Console.Write(display.PadRight(10));
Console.Write(i.ToString("X2"));
Console.WriteLine();
}
}
}
Notes, optimizations. Many optimizations can be done using ASCII codes. We can test ranges of characters with few instructions. And a lookup table (indexed by an int) can be used.
A summary. We saw all the ASCII characters. This is useful for converting between characters—such as between upper and lowercase letters—in an optimized way.
Dot Net Perls is a collection of tested code examples. Pages are continually updated to stay current, with code correctness a top priority.
Sam Allen is passionate about computer languages. In the past, his work has been recommended by Apple and Microsoft and he has studied computers at a selective university in the United States.
This page was last updated on Jun 11, 2021 (image).
