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
static string[] ExcelColumnAlphabetIdentifiers = new string[] { "", "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" };
public static string ExcelColumnAlphabetIdentifier( int ColumnNumber)
{
StringBuilder sb = new StringBuilder();
int remainder = ColumnNumber;
do
{
sb.Append(ExcelColumnAlphabetIdentifiers[remainder % 26]);
remainder = remainder / 26;
}
while (remainder > 0);
return sb.ToString();
}
其他回答
我正在尝试在Java中做同样的事情… 我写了以下代码:
private String getExcelColumnName(int columnNumber) {
int dividend = columnNumber;
String columnName = "";
int modulo;
while (dividend > 0)
{
modulo = (dividend - 1) % 26;
char val = Character.valueOf((char)(65 + modulo));
columnName += val;
dividend = (int)((dividend - modulo) / 26);
}
return columnName;
}
现在,一旦我用columnNumber = 29运行它,它给我的结果=“CA”(而不是“AC”) 有什么意见吗? 我知道我可以通过StringBuilder....反转它但看着格雷厄姆的回答,我有点困惑....
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
JavaScript解决方案
/**
* Calculate the column letter abbreviation from a 1 based index
* @param {Number} value
* @returns {string}
*/
getColumnFromIndex = function (value) {
var base = 'ABCDEFGHIJKLMNOPQRSTUVWXYZ'.split('');
var remainder, result = "";
do {
remainder = value % 26;
result = base[(remainder || 26) - 1] + result;
value = Math.floor(value / 26);
} while (value > 0);
return result;
};
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);
}
}
我想在我使用的静态类中加入,用于在col index和col Label之间进行交互。我对ColumnLabel方法使用了修改后的可接受答案
public static class Extensions
{
public static string ColumnLabel(this int col)
{
var dividend = col;
var columnLabel = string.Empty;
int modulo;
while (dividend > 0)
{
modulo = (dividend - 1) % 26;
columnLabel = Convert.ToChar(65 + modulo).ToString() + columnLabel;
dividend = (int)((dividend - modulo) / 26);
}
return columnLabel;
}
public static int ColumnIndex(this string colLabel)
{
// "AD" (1 * 26^1) + (4 * 26^0) ...
var colIndex = 0;
for(int ind = 0, pow = colLabel.Count()-1; ind < colLabel.Count(); ++ind, --pow)
{
var cVal = Convert.ToInt32(colLabel[ind]) - 64; //col A is index 1
colIndex += cVal * ((int)Math.Pow(26, pow));
}
return colIndex;
}
}
用这个…
30.ColumnLabel(); // "AD"
"AD".ColumnIndex(); // 30