如何在c#中将数值转换为Excel列名,而不使用直接从Excel中获取值的自动化。

Excel 2007的范围可能是1到16384,这是它支持的列数。结果值应以excel列名的形式出现,例如A、AA、AAA等。


当前回答

看到了另一个VBA答案-这可以在excel-vba中用1行UDF完成:

Function GetColLetter(ByVal colID As Integer) As String
    If colID > Columns.Count Then
        Err.Raise 9, , "Column index out of bounds"
    Else
        GetColLetter = Split(Cells(1, colID).Address, "$")(1)
    End If
End Function

其他回答

到目前为止,所有的解决方案都包含迭代或递归,这让我感到惊讶。

这是我的解,在常数时间内运行(没有循环)。此解决方案适用于所有可能的Excel列,并检查输入是否可以转换为Excel列。可能的列在[A, XFD]或[1,16384]范围内。(这取决于你的Excel版本)

private static string Turn(uint col)
{
    if (col < 1 || col > 16384) //Excel columns are one-based (one = 'A')
        throw new ArgumentException("col must be >= 1 and <= 16384");

    if (col <= 26) //one character
        return ((char)(col + 'A' - 1)).ToString();

    else if (col <= 702) //two characters
    {
        char firstChar = (char)((int)((col - 1) / 26) + 'A' - 1);
        char secondChar = (char)(col % 26 + 'A' - 1);

        if (secondChar == '@') //Excel is one-based, but modulo operations are zero-based
            secondChar = 'Z'; //convert one-based to zero-based

        return string.Format("{0}{1}", firstChar, secondChar);
    }

    else //three characters
    {
        char firstChar = (char)((int)((col - 1) / 702) + 'A' - 1);
        char secondChar = (char)((col - 1) / 26 % 26 + 'A' - 1);
        char thirdChar = (char)(col % 26 + 'A' - 1);

        if (thirdChar == '@') //Excel is one-based, but modulo operations are zero-based
            thirdChar = 'Z'; //convert one-based to zero-based

        return string.Format("{0}{1}{2}", firstChar, secondChar, thirdChar);
    }
}

如果有人需要在没有VBA的Excel中做到这一点,这里有一种方法:

=SUBSTITUTE(ADDRESS(1;colNum;4);"1";"")

其中colNum是列号

在VBA中:

Function GetColumnName(colNum As Integer) As String
    Dim d As Integer
    Dim m As Integer
    Dim name As String
    d = colNum
    name = ""
    Do While (d > 0)
        m = (d - 1) Mod 26
        name = Chr(65 + m) + name
        d = Int((d - m) / 26)
    Loop
    GetColumnName = name
End Function

谢谢你的回答!!帮助我想出了这些帮助函数,与我正在Elixir/Phoenix中工作的谷歌Sheets API进行一些交互

以下是我想到的(可能需要一些额外的验证和错误处理)

长生不老药:

def number_to_column(number) do
  cond do
    (number > 0 && number <= 26) ->
      to_string([(number + 64)])
    (number > 26) ->
      div_col = number_to_column(div(number - 1, 26))
      remainder = rem(number, 26)
      rem_col = cond do
        (remainder == 0) ->
          number_to_column(26)
        true ->
          number_to_column(remainder)
      end
      div_col <> rem_col
    true ->
      ""
  end
end

逆函数是:

def column_to_number(column) do
  column
    |> to_charlist
    |> Enum.reverse
    |> Enum.with_index
    |> Enum.reduce(0, fn({char, idx}, acc) ->
      ((char - 64) * :math.pow(26,idx)) + acc
    end)
    |> round
end

还有一些测试:

describe "test excel functions" do
  @excelTestData [{"A", 1}, {"Z",26}, {"AA", 27}, {"AB", 28}, {"AZ", 52},{"BA", 53}, {"AAA", 703}]

  test "column to number" do
    Enum.each(@excelTestData, fn({input, expected_result}) ->
      actual_result = BulkOnboardingController.column_to_number(input)
      assert actual_result == expected_result
    end)
  end

  test "number to column" do
    Enum.each(@excelTestData, fn({expected_result, input}) ->
      actual_result = BulkOnboardingController.number_to_column(input)
      assert actual_result == expected_result
    end)
  end
end

Objective-C实现:

-(NSString*)getColumnName:(int)n {
     NSString *name = @"";
     while (n>0) {
     n--;
     char c = (char)('A' + n%26);
     name = [NSString stringWithFormat:@"%c%@",c,name];
     n = n/26;
  }    
     return name;

}

迅速实现:

func getColumnName(n:Int)->String{
 var columnName = ""
 var index = n
 while index>0 {
     index--
     let char = Character(UnicodeScalar(65 + index%26))
     columnName = "\(char)\(columnName)"
     index = index / 26
 }
 return columnName

}

答案是基于:https://stackoverflow.com/a/4532562/2231118

在perl中,对于1 (A), 27 (AA)等输入。

sub excel_colname {
  my ($idx) = @_;       # one-based column number
  --$idx;               # zero-based column index
  my $name = "";
  while ($idx >= 0) {
    $name .= chr(ord("A") + ($idx % 26));
    $idx   = int($idx / 26) - 1;
  }
  return scalar reverse $name;
}