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。
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
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
其他回答
f#版本的各种方式
let rec getExcelColumnName x = if x<26 then int 'A'+x|>char|>string else (x/26-1|>c)+ c(x%26)
对不起,最小化,正在开发一个更好的https://stackoverflow.com/a/4500043/57883版本
相反的方向:
// return values start at 0
let getIndexFromExcelColumnName (x:string) =
let a = int 'A'
let fPow len i =
Math.Pow(26., len - 1 - i |> float)
|> int
let getValue len i c =
int c - a + 1 * fPow len i
let f i = getValue x.Length i x.[i]
[0 .. x.Length - 1]
|> Seq.map f
|> Seq.sum
|> fun x -> x - 1
以下是Graham在Powershell中的代码:
function ConvertTo-ExcelColumnID {
param (
[parameter(Position = 0,
HelpMessage = "A 1-based index to convert to an excel column ID. e.g. 2 => 'B', 29 => 'AC'",
Mandatory = $true)]
[int]$index
);
[string]$result = '';
if ($index -le 0 ) {
return $result;
}
while ($index -gt 0) {
[int]$modulo = ($index - 1) % 26;
$character = [char]($modulo + [int][char]'A');
$result = $character + $result;
[int]$index = ($index - $modulo) / 26;
}
return $result;
}
我是这样做的:
private string GetExcelColumnName(int columnNumber)
{
string columnName = "";
while (columnNumber > 0)
{
int modulo = (columnNumber - 1) % 26;
columnName = Convert.ToChar('A' + modulo) + columnName;
columnNumber = (columnNumber - modulo) / 26;
}
return columnName;
}
下面是一个基于零的列索引的更简单的解决方案
public static string GetColumnIndexNumberToExcelColumn(int columnIndex)
{
int offset = columnIndex % 26;
int multiple = columnIndex / 26;
int initialSeed = 65;//Represents column "A"
if (multiple == 0)
{
return Convert.ToChar(initialSeed + offset).ToString();
}
return $"{Convert.ToChar(initialSeed + multiple - 1)}{Convert.ToChar(initialSeed + offset)}";
}
public string ToBase26(int number)
{
if (number < 0) return String.Empty;
int remainder = number % 26;
int value = number / 26;
return value == 0 ?
String.Format("{0}", Convert.ToChar(65 + remainder)) :
String.Format("{0}{1}", ToBase26(value - 1), Convert.ToChar(65 + remainder));
}