给定一个字符串，将其转换为4字节块中的十六进制..C#
本文关键字：字节 转换 十六进制 字符串 一个 | 更新日期: 2023-09-27 18:22:15
我是一个初学者爱好者，最近一直在研究我的代码中的一个问题。我的代码丑陋且效率低下，主要是因为我缺乏经验。然而，我喜欢这个东西。
问题：给定一个字符串，我可以成功地转换为十六进制。然而，我希望给定的字符串（尽管它的长度）能够转换为Hex中的4字节块。对于字符串大于一个字节但小于4个字节的情况，我想在字符串右侧加上"0"。我发现只要我操作PadRight方法的totalWidth参数，我就只能部分成功。如果没有额外的块，其中只有零，我如何才能实现我所追求的？
请参阅下面我使用的确切代码示例：
// create a char array using the string provided to the encoder method
char[] arrayCharValues = strMessage.ToCharArray();
// create stringbuilder object
StringBuilder sb = new StringBuilder();
// iterate through each char and convert it to int32 then to Hex then append to stringbuilder object.
foreach (char c in arrayCharValues)
{
// convert char to int32
int intCharToNumVal = Convert.ToInt32(c);
// convert int32 to hex
string strNumToHexVal = String.Format("{0:X2}", intCharToNumVal);
// append hex value to string builder object
sb.Append(strNumToHexVal);
}
string s = sb.ToString();
if (s.Length % 8 == 0)
{
var list = Enumerable
.Range(0, s.Length / 8)
.Select(i => s.Substring(i * 8, 8))
.ToList();
var res = string.Join(" ", list);
// DEBUG: echo results for testing.
Console.WriteLine("");
Console.WriteLine("String provided: {0}", strMessage);
Console.WriteLine("String provided total length: {0}", s.Length);
Console.WriteLine("Hex equivalent of string provided: {0}", sb.ToString());
Console.WriteLine("Hex in 8-digit chunks: {0}", res.ToString());
Console.WriteLine("======================================================");
}
else
{
int intDivisibleByEight = s.Length % 8;
int intPadRight = (8 - intDivisibleByEight) / 2;
char pad = '0';
//BUG: doesn't know how to handle anything over 16 bits. If I use an input string of "coolsssss" i get 636F6F6C 73737373 73000000 00000000
//BUG: <cont'd> if i use the same input string and change the PadRight(32,pad) to PadRight(16,pad) i get 636F6F6C 73737373 and the final chunk is ignored.
//BUG: <cont'd> I want it to work as it does with the PadRight(32, pad) method but, I want it to ignore the all zeros chunk(s) that may follow.
//NOTE: int totalWidth = the number of characters i nthe resulting string, equal to the number of original characters plus any additional padding characters.
s = s.PadRight(32, pad);
var list = Enumerable
.Range(0, s.Length / 8)
.Select(i => s.Substring(i * 8, 8))
.ToList();
var res = string.Join(" ", list);
// DEBUG: echo results for testing.
Console.WriteLine("");
Console.WriteLine("String provided: {0}", strMessage);
Console.WriteLine("String provided total length: {0}", s.Length);
Console.WriteLine("Hex equivalent of string provided: {0}", sb.ToString());
Console.WriteLine("Hex in 8-digit chunks: {0}", res.ToString());
Console.WriteLine("======================================================");
}
虽然所有这些.Range.Select都很有趣，但有时更容易恢复到简单的旧循环。分块结果不需要hexedString，我添加它只是为了显示不需要分块时的差异。
string strMessage = "coolsssss";
string hexedString = string.Join("", strMessage.Select(c => String.Format("{0:X2}", (int)c)))
.PadRight((strMessage.Length + 3) / 4 * 8, '0');
StringBuilder sb = new StringBuilder(strMessage.Length * 9 / 4 + 10);
int count = 0;
foreach (char c in strMessage)
{
if (count == 4)
{
sb.Append(" ");
count = 0;
}
sb.Append(String.Format("{0:X2}", (int)c));
count++;
}
for (int i = 0; i < (4 - count) % 4; ++i)
{
sb.Append("00");
}
// DEBUG: echo results for testing.
Console.WriteLine("");
Console.WriteLine("String provided: {0}", strMessage);
Console.WriteLine("Hex equivalent of string provided: {0}", hexedString);
Console.WriteLine("Hex in 8-digit chunks: {0}", sb.ToString());
Console.WriteLine("======================================================");
编辑：
在@GabrielAlicea的提问中，我补充了一些解释。
new StringBuilder(strMessage.Length * 9 / 4 + 10);
这基本上创建了StringBuilder，并将内存预先分配到所需的大小。我们从4个字母加上空格得到8位数字，这里是9/4。再加上一些四的填充物。计算不精确，如果你愿意，你可以精确地做。预先分配动态增长的对象是一个好习惯，比如List、StringBuilder、Dictionary。。。如果你事先知道尺寸。例如，List在内部使用数组。当填充时，它会得到两倍大小的数组，并将所有内容复制到其中。当您提前知道必要的大小时，这是在浪费时间。使用StringBuilder会更复杂（取决于.net版本），但无论如何，预分配都是个好主意。
(int i = 0; i < (4 - count) % 4; ++i)
计数是最后一块中的字母数。我们为每个缺失的字母加两个零，这意味着(4 - count)次。它适用于空字符串，其中count等于0，(4 - count)等于4。所以我添加了% 4来处理这个特定的情况。
对于你的代码，你可能想写这样的：
int intPadRight = 8 - intDivisibleByEight;
这个：
s = s.PadRight(s.Length + intPadRight, pad);
但是您可以将% 8添加到intPadRight中，并完全消除if (s.Length % 8 == 0)：
...
string s = sb.ToString();
int intDivisibleByEight = s.Length % 8;
int intPadRight = (8 - intDivisibleByEight) % 8;
char pad = '0';
s = s.PadRight(s.Length + intPadRight, pad);
var list = Enumerable
.Range(0, s.Length / 8)
.Select(i => s.Substring(i * 8, 8))
.ToList();
var res = string.Join(" ", list);
// DEBUG: echo results for testing.
Console.WriteLine("");
Console.WriteLine("String provided: {0}", strMessage);
Console.WriteLine("String provided total length: {0}", s.Length);
Console.WriteLine("Hex equivalent of string provided: {0}", sb.ToString());
Console.WriteLine("Hex in 8-digit chunks: {0}", res.ToString());
Console.WriteLine("======================================================");