我和旧的（ish）C＃方法我写了一个数字并将其转换为任何基数：
string ConvertToBase(int number, char[] baseChars);
并不是那么超级快速和整洁。在.NET中有没有一种很好的，已知的实现方法？
我正在寻找允许我使用任何基础并使用任意字符串的东西。
这只允许碱基16,10,8和2：
Convert.ToString(1, x);
我想利用它来利用数字，全部小写和全部大写字母来实现高基数。就像在this thread中一样，但对于C＃而不是JavaScript。
有没有人知道在C＃中这样做的好方法？
答案 0 :(得分：119)
Convert.ToString可用于将数字转换为指定基数中的等效字符串表示形式。
示例：
string binary = Convert.ToString(5, 2); // convert 5 to its binary representation
Console.WriteLine(binary); // prints 101
然而，正如评论所指出的那样，Convert.ToString仅支持以下有限的 - 但通常是足够的 - 基础集：2个，8个，10个或16个。
我不知道BCL中的任何方法能够将数字转换为任何基数，因此您必须编写自己的小实用程序函数。一个简单的样本看起来就像那样（请注意，通过替换字符串连接，这肯定可以更快）：
class Program
{
static void Main(string[] args)
{
// convert to binary
string binary = IntToString(42, new char[] { '0', '1' });
// convert to hexadecimal
string hex = IntToString(42,
new char[] { '0', '1', '2', '3', '4', '5', '6', '7', '8', '9',
'A', 'B', 'C', 'D', 'E', 'F'});
// convert to hexavigesimal (base 26, A-Z)
string hexavigesimal = IntToString(42,
Enumerable.Range('A', 26).Select(x => (char)x).ToArray());
// convert to sexagesimal
string xx = IntToString(42,
new char[] { '0','1','2','3','4','5','6','7','8','9',
'A','B','C','D','E','F','G','H','I','J','K','L','M','N','O','P','Q','R','S','T','U','V','W','X','Y','Z',
'a','b','c','d','e','f','g','h','i','j','k','l','m','n','o','p','q','r','s','t','u','v','w','x'});
}
public static string IntToString(int value, char[] baseChars)
{
string result = string.Empty;
int targetBase = baseChars.Length;
do
{
result = baseChars[value % targetBase] + result;
value = value / targetBase;
}
while (value > 0);
return result;
}
/// <summary>
/// An optimized method using an array as buffer instead of
/// string concatenation. This is faster for return values having
/// a length > 1.
/// </summary>
public static string IntToStringFast(int value, char[] baseChars)
{
// 32 is the worst cast buffer size for base 2 and int.MaxValue
int i = 32;
char[] buffer = new char[i];
int targetBase= baseChars.Length;
do
{
buffer[--i] = baseChars[value % targetBase];
value = value / targetBase;
}
while (value > 0);
char[] result = new char[32 - i];
Array.Copy(buffer, i, result, 0, 32 - i);
return new string(result);
}
}
使用数组缓冲区而不是字符串连接来构建结果字符串可以提高性能，特别是对于大数字（参见方法IntToStringFast）。在最好的情况下（即最长的输入），这种方法大约快三倍。但是，对于1位数字（即目标基数中的1位数），IntToString将更快。
答案 1 :(得分：67)
I recently blogged about this。我的实现在计算过程中不使用任何字符串操作，这使得非常快。允许转换为基数为2到36的任何数字系统：
/// <summary>
/// Converts the given decimal number to the numeral system with the
/// specified radix (in the range [2, 36]).
/// </summary>
/// <param name="decimalNumber">The number to convert.</param>
/// <param name="radix">The radix of the destination numeral system (in the range [2, 36]).</param>
/// <returns></returns>
public static string DecimalToArbitrarySystem(long decimalNumber, int radix)
{
const int BitsInLong = 64;
const string Digits = "0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ";
if (radix < 2 || radix > Digits.Length)
throw new ArgumentException("The radix must be >= 2 and <= " + Digits.Length.ToString());
if (decimalNumber == 0)
return "0";
int index = BitsInLong - 1;
long currentNumber = Math.Abs(decimalNumber);
char[] charArray = new char[BitsInLong];
while (currentNumber != 0)
{
int remainder = (int)(currentNumber % radix);
charArray[index--] = Digits[remainder];
currentNumber = currentNumber / radix;
}
string result = new String(charArray, index + 1, BitsInLong - index - 1);
if (decimalNumber < 0)
{
result = "-" + result;
}
return result;
}
我也实现了快速反转功能，以防任何人需要它： Arbitrary to Decimal Numeral System
答案 2 :(得分：7)
也可以使用已接受版本的略微修改版本，并根据需要调整基本字符串：
public static string Int32ToString(int value, int toBase)
{
string result = string.Empty;
do
{
result = "0123456789ABCDEF"[value % toBase] + result;
value /= toBase;
}
while (value > 0);
return result;
}
答案 3 :(得分：5)
FAST“ FROM ”和“ TO ”方法
我迟到了，但我复习了以前的答案，并改进了它们。我认为这两种方法比目前为止发布的其他方法都快。我能够在一台核心机器中将400,000个数字从400毫秒转换为36个基数。
以下示例适用于 base 62 。更改BaseChars数组以转换为任何其他基础。
private static readonly char[] BaseChars =
"0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz".ToCharArray();
private static readonly Dictionary<char, int> CharValues = BaseChars
.Select((c,i)=>new {Char=c, Index=i})
.ToDictionary(c=>c.Char,c=>c.Index);
public static string LongToBase(long value)
{
long targetBase = BaseChars.Length;
// Determine exact number of characters to use.
char[] buffer = new char[Math.Max(
(int) Math.Ceiling(Math.Log(value + 1, targetBase)), 1)];
var i = buffer.Length;
do
{
buffer[--i] = BaseChars[value % targetBase];
value = value / targetBase;
}
while (value > 0);
return new string(buffer, i, buffer.Length - i);
}
public static long BaseToLong(string number)
{
char[] chrs = number.ToCharArray();
int m = chrs.Length - 1;
int n = BaseChars.Length, x;
long result = 0;
for (int i = 0; i < chrs.Length; i++)
{
x = CharValues[ chrs[i] ];
result += x * (long)Math.Pow(n, m--);
}
return result;
}
编辑（2018-07-12）
已修复以解决由@AdrianBotor（请参阅注释）将46655转换为基数36所发现的极端情况。这是由计算Math.Log(46656, 36)的小浮点错误引起的，该错误正好为3，但.NET返回{{ 1}}，这会在输出缓冲区中产生额外的字符。
答案 4 :(得分：4)
关于这一方的聚会很晚，但我最近写了一个关于工作项目的帮助班。它被设计为将短字符串转换为数字并再次返回（简单的perfect hash函数），但它也将执行任意基数之间的数字转换。 Base10ToString方法实现回答了最初发布的问题。
需要传递给类构造函数的shouldSupportRoundTripping标志，以防止在转换为base-10期间从数字字符串中丢失前导数字，然后再返回（至关重要，根据我的要求！）。大多数情况下，从数字字符串中丢失前导0可能不是问题。
无论如何，这是代码：
using System;
using System.Collections.Generic;
using System.Linq;
namespace StackOverflow
{
/// <summary>
/// Contains methods used to convert numbers between base-10 and another numbering system.
/// </summary>
/// <remarks>
/// <para>
/// This conversion class makes use of a set of characters that represent the digits used by the target
/// numbering system. For example, binary would use the digits 0 and 1, whereas hex would use the digits
/// 0 through 9 plus A through F. The digits do not have to be numerals.
/// </para>
/// <para>
/// The first digit in the sequence has special significance. If the number passed to the
/// <see cref="StringToBase10"/> method has leading digits that match the first digit, then those leading
/// digits will effectively be 'lost' during conversion. Much of the time this won't matter. For example,
/// "0F" hex will be converted to 15 decimal, but when converted back to hex it will become simply "F",
/// losing the leading "0". However, if the set of digits was A through Z, and the number "ABC" was
/// converted to base-10 and back again, then the leading "A" would be lost. The <see cref="System.Boolean"/>
/// flag passed to the constructor allows 'round-tripping' behaviour to be supported, which will prevent
/// leading digits from being lost during conversion.
/// </para>
/// <para>
/// Note that numeric overflow is probable when using longer strings and larger digit sets.
/// </para>
/// </remarks>
public class Base10Converter
{
const char NullDigit = '\0';
public Base10Converter(string digits, bool shouldSupportRoundTripping = false)
: this(digits.ToCharArray(), shouldSupportRoundTripping)
{
}
public Base10Converter(IEnumerable<char> digits, bool shouldSupportRoundTripping = false)
{
if (digits == null)
{
throw new ArgumentNullException("digits");
}
if (digits.Count() == 0)
{
throw new ArgumentException(
message: "The sequence is empty.",
paramName: "digits"
);
}
if (!digits.Distinct().SequenceEqual(digits))
{
throw new ArgumentException(
message: "There are duplicate characters in the sequence.",
paramName: "digits"
);
}
if (shouldSupportRoundTripping)
{
digits = (new[] { NullDigit }).Concat(digits);
}
_digitToIndexMap =
digits
.Select((digit, index) => new { digit, index })
.ToDictionary(keySelector: x => x.digit, elementSelector: x => x.index);
_radix = _digitToIndexMap.Count;
_indexToDigitMap =
_digitToIndexMap
.ToDictionary(keySelector: x => x.Value, elementSelector: x => x.Key);
}
readonly Dictionary<char, int> _digitToIndexMap;
readonly Dictionary<int, char> _indexToDigitMap;
readonly int _radix;
public long StringToBase10(string number)
{
Func<char, int, long> selector =
(c, i) =>
{
int power = number.Length - i - 1;
int digitIndex;
if (!_digitToIndexMap.TryGetValue(c, out digitIndex))
{
throw new ArgumentException(
message: String.Format("Number contains an invalid digit '{0}' at position {1}.", c, i),
paramName: "number"
);
}
return Convert.ToInt64(digitIndex * Math.Pow(_radix, power));
};
return number.Select(selector).Sum();
}
public string Base10ToString(long number)
{
if (number < 0)
{
throw new ArgumentOutOfRangeException(
message: "Value cannot be negative.",
paramName: "number"
);
}
string text = string.Empty;
long remainder;
do
{
number = Math.DivRem(number, _radix, out remainder);
char digit;
if (!_indexToDigitMap.TryGetValue((int) remainder, out digit) || digit == NullDigit)
{
throw new ArgumentException(
message: "Value cannot be converted given the set of digits used by this converter.",
paramName: "number"
);
}
text = digit + text;
}
while (number > 0);
return text;
}
}
}
这也可以是子类，以派生自定义数字转换器：
namespace StackOverflow
{
public sealed class BinaryNumberConverter : Base10Converter
{
public BinaryNumberConverter()
: base(digits: "01", shouldSupportRoundTripping: false)
{
}
}
public sealed class HexNumberConverter : Base10Converter
{
public HexNumberConverter()
: base(digits: "0123456789ABCDEF", shouldSupportRoundTripping: false)
{
}
}
}
代码将像这样使用：
using System.Diagnostics;
namespace StackOverflow
{
class Program
{
static void Main(string[] args)
{
{
var converter = new Base10Converter(
digits: "ABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789abcdefghijklmnopqrstuvwxyz",
shouldSupportRoundTripping: true
);
long number = converter.StringToBase10("Atoz");
string text = converter.Base10ToString(number);
Debug.Assert(text == "Atoz");
}
{
var converter = new HexNumberConverter();
string text = converter.Base10ToString(255);
long number = converter.StringToBase10(text);
Debug.Assert(number == 255);
}
}
}
}
答案 5 :(得分：2)
this forum post的这门课可以帮助你吗？
public class BaseConverter {
public static string ToBase(string number, int start_base, int target_base) {
int base10 = this.ToBase10(number, start_base);
string rtn = this.FromBase10(base10, target_base);
return rtn;
}
public static int ToBase10(string number, int start_base) {
if (start_base < 2 || start_base > 36) return 0;
if (start_base == 10) return Convert.ToInt32(number);
char[] chrs = number.ToCharArray();
int m = chrs.Length - 1;
int n = start_base;
int x;
int rtn = 0;
foreach(char c in chrs) {
if (char.IsNumber(c))
x = int.Parse(c.ToString());
else
x = Convert.ToInt32(c) - 55;
rtn += x * (Convert.ToInt32(Math.Pow(n, m)));
m--;
}
return rtn;
}
public static string FromBase10(int number, int target_base) {
if (target_base < 2 || target_base > 36) return "";
if (target_base == 10) return number.ToString();
int n = target_base;
int q = number;
int r;
string rtn = "";
while (q >= n) {
r = q % n;
q = q / n;
if (r < 10)
rtn = r.ToString() + rtn;
else
rtn = Convert.ToChar(r + 55).ToString() + rtn;
}
if (q < 10)
rtn = q.ToString() + rtn;
else
rtn = Convert.ToChar(q + 55).ToString() + rtn;
return rtn;
}
}
完全未经测试......让我知道它是否有效！ （复制粘贴它以防论坛帖子消失或者某事......）
答案 6 :(得分：1)
我也在寻找一种快速的方法将十进制数转换为[2..36]范围内的另一个基数，所以我开发了以下代码。它很容易遵循并使用Stringbuilder对象作为字符缓冲区的代理，我们可以逐个字符地索引。与替代方案相比，代码看起来非常快，并且比在字符数组中初始化单个字符要快得多。
为了您自己的使用，您可能更愿意： 1 /返回空字符串而不是抛出异常。 2 /删除基数检查以使方法运行得更快 3 /使用32'0初始化Stringbuilder对象并删除行result.Remove（0，i）;。这将导致字符串返回前导零并进一步提高速度。 4 /使Stringbuilder对象成为类中的静态字段，因此无论调用DecimalToBase方法多少次，Stringbuilder对象仅初始化一次。如果你这样做，上面的3改变将不再起作用。
我希望有人觉得这很有用：）
AtomicParadox
static string DecimalToBase(int number, int radix)
{
// Check that the radix is between 2 and 36 inclusive
if ( radix < 2 || radix > 36 )
throw new ArgumentException("ConvertToBase(int number, int radix) - Radix must be between 2 and 36.");
// Create a buffer large enough to hold the largest int value represented in binary digits
StringBuilder result = new StringBuilder(" "); // 32 spaces
// The base conversion calculates the digits in reverse order so use
// an index to point to the last unused space in our buffer
int i = 32;
// Convert the number to the new base
do
{
int remainder = number % radix;
number = number / radix;
if(remainder <= 9)
result[--i] = (char)(remainder + '0'); // Converts [0..9] to ASCII ['0'..'9']
else
result[--i] = (char)(remainder + '7'); // Converts [10..36] to ASCII ['A'..'Z']
} while ( number > 0 );
// Remove the unwanted padding from the front of our buffer and return the result
// Note i points to the last unused character in our buffer
result.Remove( 0, i );
return (result.ToString());
}
答案 7 :(得分：0)
我使用它来将Guid存储为较短的字符串（但仅限于使用106个字符）。 如果有人对此感兴趣，那么我的代码是将字符串解码回数值（在这种情况下，我使用2 ulongs作为Guid值，而不是编码Int128（因为我在3.5而不是4.0）。 为清楚起见，CODE是一个包含106个唯一字符的字符串const。 ConvertLongsToBytes非常令人兴奋。
private static Guid B106ToGuid(string pStr)
{
try
{
ulong tMutl = 1, tL1 = 0, tL2 = 0, targetBase = (ulong)CODE.Length;
for (int i = 0; i < pStr.Length / 2; i++)
{
tL1 += (ulong)CODE.IndexOf(pStr[i]) * tMutl;
tL2 += (ulong)CODE.IndexOf(pStr[pStr.Length / 2 + i]) * tMutl;
tMutl *= targetBase;
}
return new Guid(ConvertLongsToBytes(tL1, tL2));
}
catch (Exception ex)
{
throw new Exception("B106ToGuid failed to convert string to Guid", ex);
}
}
答案 8 :(得分：0)
我有类似的需求，除了我需要对“数字”进行数学运算。我在这里提出了一些建议并创建了一个可以完成所有这些有趣内容的课程。它允许使用任何unicode字符来表示数字，它也适用于小数。
这个类很容易使用。只需创建一个New BaseNumber类型的数字，设置一些属性，然后关闭。例程负责自动在基数10和基数x之间切换，你设置的值保存在你设置的基数中，因此不会丢失精度（直到转换为止，但即使这样，精度损失应该非常小，因为这样例行程序尽可能使用Double和Long。
我无法控制这个例程的速度。它可能很慢，所以我不确定它是否适合提问的人的需要，但它肯定是灵活的，所以希望其他人可以使用它。
对于其他可能需要此代码来计算Excel中下一列的人，我将包含我使用的利用此类的循环代码。
Public Class BaseNumber
Private _CharacterArray As List(Of Char)
Private _BaseXNumber As String
Private _Base10Number As Double?
Private NumberBaseLow As Integer
Private NumberBaseHigh As Integer
Private DecimalSeparator As Char = System.Globalization.CultureInfo.CurrentCulture.NumberFormat.NumberDecimalSeparator
Private GroupSeparator As Char = System.Globalization.CultureInfo.CurrentCulture.NumberFormat.NumberGroupSeparator
Public Sub UseCapsLetters()
'http://unicodelookup.com
TrySetBaseSet(65, 90)
End Sub
Public Function GetCharacterArray() As List(Of Char)
Return _CharacterArray
End Function
Public Sub SetCharacterArray(CharacterArray As String)
_CharacterArray = New List(Of Char)
_CharacterArray.AddRange(CharacterArray.ToList)
TrySetBaseSet(_CharacterArray)
End Sub
Public Sub SetCharacterArray(CharacterArray As List(Of Char))
_CharacterArray = CharacterArray
TrySetBaseSet(_CharacterArray)
End Sub
Public Sub SetNumber(Value As String)
_BaseXNumber = Value
_Base10Number = Nothing
End Sub
Public Sub SetNumber(Value As Double)
_Base10Number = Value
_BaseXNumber = Nothing
End Sub
Public Function GetBaseXNumber() As String
If _BaseXNumber IsNot Nothing Then
Return _BaseXNumber
Else
Return ToBaseString()
End If
End Function
Public Function GetBase10Number() As Double
If _Base10Number IsNot Nothing Then
Return _Base10Number
Else
Return ToBase10()
End If
End Function
Private Sub TrySetBaseSet(Values As List(Of Char))
For Each value As Char In _BaseXNumber
If Not Values.Contains(value) Then
Throw New ArgumentOutOfRangeException("The string has a value, " & value & ", not contained in the selected 'base' set.")
_CharacterArray.Clear()
DetermineNumberBase()
End If
Next
_CharacterArray = Values
End Sub
Private Sub TrySetBaseSet(LowValue As Integer, HighValue As Integer)
Dim HighLow As KeyValuePair(Of Integer, Integer) = GetHighLow()
If HighLow.Key < LowValue OrElse HighLow.Value > HighValue Then
Throw New ArgumentOutOfRangeException("The string has a value not contained in the selected 'base' set.")
_CharacterArray.Clear()
DetermineNumberBase()
End If
NumberBaseLow = LowValue
NumberBaseHigh = HighValue
End Sub
Private Function GetHighLow(Optional Values As List(Of Char) = Nothing) As KeyValuePair(Of Integer, Integer)
If Values Is Nothing Then
Values = _BaseXNumber.ToList
End If
Dim lowestValue As Integer = Convert.ToInt32(Values(0))
Dim highestValue As Integer = Convert.ToInt32(Values(0))
Dim currentValue As Integer
For Each value As Char In Values
If value <> DecimalSeparator AndAlso value <> GroupSeparator Then
currentValue = Convert.ToInt32(value)
If currentValue > highestValue Then
highestValue = currentValue
End If
If currentValue < lowestValue Then
currentValue = lowestValue
End If
End If
Next
Return New KeyValuePair(Of Integer, Integer)(lowestValue, highestValue)
End Function
Public Sub New(BaseXNumber As String)
_BaseXNumber = BaseXNumber
DetermineNumberBase()
End Sub
Public Sub New(BaseXNumber As String, NumberBase As Integer)
Me.New(BaseXNumber, Convert.ToInt32("0"c), NumberBase)
End Sub
Public Sub New(BaseXNumber As String, NumberBaseLow As Integer, NumberBaseHigh As Integer)
_BaseXNumber = BaseXNumber
Me.NumberBaseLow = NumberBaseLow
Me.NumberBaseHigh = NumberBaseHigh
End Sub
Public Sub New(Base10Number As Double)
_Base10Number = Base10Number
End Sub
Private Sub DetermineNumberBase()
Dim highestValue As Integer
Dim currentValue As Integer
For Each value As Char In _BaseXNumber
currentValue = Convert.ToInt32(value)
If currentValue > highestValue Then
highestValue = currentValue
End If
Next
NumberBaseHigh = highestValue
NumberBaseLow = Convert.ToInt32("0"c) 'assume 0 is the lowest
End Sub
Private Function ToBaseString() As String
Dim Base10Number As Double = _Base10Number
Dim intPart As Long = Math.Truncate(Base10Number)
Dim fracPart As Long = (Base10Number - intPart).ToString.Replace(DecimalSeparator, "")
Dim intPartString As String = ConvertIntToString(intPart)
Dim fracPartString As String = If(fracPart <> 0, DecimalSeparator & ConvertIntToString(fracPart), "")
Return intPartString & fracPartString
End Function
Private Function ToBase10() As Double
Dim intPartString As String = _BaseXNumber.Split(DecimalSeparator)(0).Replace(GroupSeparator, "")
Dim fracPartString As String = If(_BaseXNumber.Contains(DecimalSeparator), _BaseXNumber.Split(DecimalSeparator)(1), "")
Dim intPart As Long = ConvertStringToInt(intPartString)
Dim fracPartNumerator As Long = ConvertStringToInt(fracPartString)
Dim fracPartDenominator As Long = ConvertStringToInt(GetEncodedChar(1) & String.Join("", Enumerable.Repeat(GetEncodedChar(0), fracPartString.ToString.Length)))
Return Convert.ToDouble(intPart + fracPartNumerator / fracPartDenominator)
End Function
Private Function ConvertIntToString(ValueToConvert As Long) As String
Dim result As String = String.Empty
Dim targetBase As Long = GetEncodingCharsLength()
Do
result = GetEncodedChar(ValueToConvert Mod targetBase) & result
ValueToConvert = ValueToConvert \ targetBase
Loop While ValueToConvert > 0
Return result
End Function
Private Function ConvertStringToInt(ValueToConvert As String) As Long
Dim result As Long
Dim targetBase As Integer = GetEncodingCharsLength()
Dim startBase As Integer = GetEncodingCharsStartBase()
Dim value As Char
For x As Integer = 0 To ValueToConvert.Length - 1
value = ValueToConvert(x)
result += GetDecodedChar(value) * Convert.ToInt32(Math.Pow(GetEncodingCharsLength, ValueToConvert.Length - (x + 1)))
Next
Return result
End Function
Private Function GetEncodedChar(index As Integer) As Char
If _CharacterArray IsNot Nothing AndAlso _CharacterArray.Count > 0 Then
Return _CharacterArray(index)
Else
Return Convert.ToChar(index + NumberBaseLow)
End If
End Function
Private Function GetDecodedChar(character As Char) As Integer
If _CharacterArray IsNot Nothing AndAlso _CharacterArray.Count > 0 Then
Return _CharacterArray.IndexOf(character)
Else
Return Convert.ToInt32(character) - NumberBaseLow
End If
End Function
Private Function GetEncodingCharsLength() As Integer
If _CharacterArray IsNot Nothing AndAlso _CharacterArray.Count > 0 Then
Return _CharacterArray.Count
Else
Return NumberBaseHigh - NumberBaseLow + 1
End If
End Function
Private Function GetEncodingCharsStartBase() As Integer
If _CharacterArray IsNot Nothing AndAlso _CharacterArray.Count > 0 Then
Return GetHighLow.Key
Else
Return NumberBaseLow
End If
End Function
End Class
现在代码循环遍历Excel列：
Public Function GetColumnList(DataSheetID As String) As List(Of String)
Dim workingColumn As New BaseNumber("A")
workingColumn.SetCharacterArray("@ABCDEFGHIJKLMNOPQRSTUVWXYZ")
Dim listOfPopulatedColumns As New List(Of String)
Dim countOfEmptyColumns As Integer
Dim colHasData As Boolean
Dim cellHasData As Boolean
Do
colHasData = True
cellHasData = False
For r As Integer = 1 To GetMaxRow(DataSheetID)
cellHasData = cellHasData Or XLGetCellValue(DataSheetID, workingColumn.GetBaseXNumber & r) <> ""
Next
colHasData = colHasData And cellHasData
'keep trying until we get 4 empty columns in a row
If colHasData Then
listOfPopulatedColumns.Add(workingColumn.GetBaseXNumber)
countOfEmptyColumns = 0
Else
countOfEmptyColumns += 1
End If
'we are already starting with column A, so increment after we check column A
Do
workingColumn.SetNumber(workingColumn.GetBase10Number + 1)
Loop Until Not workingColumn.GetBaseXNumber.Contains("@")
Loop Until countOfEmptyColumns > 3
Return listOfPopulatedColumns
End Function
您会注意到Excel部分的重要部分是0在基于重新编号的数字中由@标识。所以我只过滤掉所有带有@的数字，然后得到正确的序列（A，B，C，...，Z，AA，AB，AC，......）。
答案 9 :(得分：0)
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
namespace ConvertToAnyBase
{
class Program
{
static void Main(string[] args)
{
var baseNumber = int.Parse(Console.ReadLine());
var number = int.Parse(Console.ReadLine());
string conversion = "";
while(number!=0)
{
conversion += Convert.ToString(number % baseNumber);
number = number / baseNumber;
}
var conversion2 = conversion.ToArray().Reverse();
Console.WriteLine(string.Join("", conversion2));
}
}
}
答案 10 :(得分：-1)
如果有人在寻求VB选项，则基于Pavel的回答：
Public Shared Function ToBase(base10 As Long, Optional baseChars As String = "0123456789ABCDEFGHIJKLMNOPQRTSUVWXYZ") As String
If baseChars.Length < 2 Then Throw New ArgumentException("baseChars must be at least 2 chars long")
If base10 = 0 Then Return baseChars(0)
Dim isNegative = base10 < 0
Dim radix = baseChars.Length
Dim index As Integer = 64 'because it's how long a string will be if the basechars are 2 long (binary)
Dim chars(index) As Char '65 chars, 64 from above plus one for sign if it's negative
base10 = Math.Abs(base10)
While base10 > 0
chars(index) = baseChars(base10 Mod radix)
base10 \= radix
index -= 1
End While
If isNegative Then
chars(index) = "-"c
index -= 1
End If
Return New String(chars, index + 1, UBound(chars) - index)
End Function
答案 11 :(得分：-1)
这是一种相当简单的方法，但是可能不是最快的方法。它非常强大，因为它可以组合。
public static IEnumerable<int> ToBase(this int x, int b)
{
IEnumerable<int> ToBaseReverse()
{
if (x == 0)
{
yield return 0;
yield break;
}
int z = x;
while (z > 0)
{
yield return z % b;
z = z / b;
}
}
return ToBaseReverse().Reverse();
}
使用这种简单的扩展方法将其组合起来，现在就可以得到任何基础：
public static string ToBase(this int number, string digits) =>
String.Concat(number.ToBase(digits.Length).Select(x => digits[x]));
可以这样使用：
var result = 23.ToBase("01");
var result2 = 23.ToBase("012X");
Console.WriteLine(result);
Console.WriteLine(result2);
输出为：
10111 11X