这里的主要问题是,ApachePOI没有提供使用AS ArrayFunction
的所有功能.在该特殊情况下,Excel function ROW由Java
函数org.apache.poi.ss.formula.functions.RowFunc表示,该函数org.apache.poi.ss.formula.functions.RowFunc未准备好在数组上下文中运行.
这可以通过更改Java
函数的代码来更改.该代码需要考虑"如果Reference是一个单元格区域,并且如果以垂直数组的形式输入row,则row以垂直数组的形式返回引用的行号."我的函数RowFuncArrayReady
可以做到这一点.
import org.apache.poi.ss.formula.functions.*;
import org.apache.poi.ss.formula.eval.AreaEval;
import org.apache.poi.ss.formula.eval.ErrorEval;
import org.apache.poi.ss.formula.eval.NumberEval;
import org.apache.poi.ss.formula.eval.RefEval;
import org.apache.poi.ss.formula.eval.ValueEval;
import org.apache.poi.ss.formula.CacheAreaEval;
/**
* Implementation for the Excel function ROW ready for usage as ArrayFunction
*/
public final class RowFuncArrayReady implements Function, ArrayFunction {
@Override
public ValueEval evaluate(ValueEval[] args, int srcRowIndex, int srcColumnIndex) {
if (args.length > 1) {
return ErrorEval.VALUE_INVALID;
}
if (args.length == 0) {
return new NumberEval(srcRowIndex + 1.);
} else {
return evaluate(srcRowIndex, srcColumnIndex, args[0]);
}
}
public ValueEval evaluate(int srcRowIndex, int srcColumnIndex, ValueEval arg0) {
int rnum;
if (arg0 instanceof AreaEval) {
rnum = ((AreaEval)arg0).getFirstRow();
} else if (arg0 instanceof RefEval) {
rnum = ((RefEval)arg0).getRow();
} else {
// anything else is not valid argument
return ErrorEval.VALUE_INVALID;
}
return new NumberEval(rnum + 1.);
}
@Override
public ValueEval evaluateArray(ValueEval[] args, int srcRowIndex, int srcColumnIndex) {
if (args.length > 1) {
return ErrorEval.VALUE_INVALID;
}
if (args.length == 0) {
return new NumberEval(srcRowIndex + 1.);
} else if (args[0] instanceof AreaEval) {
return evaluateAreaEval((AreaEval)args[0], srcRowIndex, srcColumnIndex);
} else if (args[0] instanceof RefEval) {
return evaluate(srcRowIndex, srcColumnIndex, (RefEval)args[0]);
} else {
// anything else is not valid argument
return ErrorEval.VALUE_INVALID;
}
}
private ValueEval evaluateAreaEval(AreaEval ae, int srcRowIndex, int srcColumnIndex) {
int w1, w2, h1, h2;
int a1FirstCol = 0, a1FirstRow = 0;
w1 = ae.getWidth();
h1 = ae.getHeight();
a1FirstCol = ae.getFirstColumn();
a1FirstRow = ae.getFirstRow();
w2 = 1;
h2 = 1;
int width = Math.max(w1, w2);
int height = Math.max(h1, h2);
ValueEval[] vals = new ValueEval[height * width];
int idx = 0;
for(int i = 0; i < height; i++){
for(int j = 0; j < width; j++){
vals[idx++] = evaluate(srcRowIndex, srcColumnIndex, ae.offset(i, i, j, j));
}
}
if (vals.length == 1) {
return vals[0];
}
return new CacheAreaEval(srcRowIndex, srcColumnIndex, srcRowIndex + height - 1, srcColumnIndex + width - 1, vals);
}
}
要使该新函数成为Excel的ROW函数的默认表示形式,它需要位于索引8处的Function[] functions
个org.apache.poi.ss.formula.eval.FunctionEval数组中.在下面的代码中,方法prepareFunctionEval
将在被调用为prepareFunctionEval(8, new RowFuncArrayReady());
时执行此操作.
import org.apache.poi.ss.usermodel.*;
import java.io.FileInputStream;
class ExcelEvaluateROWFormulaAsArray {
static void prepareFunctionEval(int pos, org.apache.poi.ss.formula.functions.Function function) throws Exception {
java.lang.reflect.Field _functions = Class.forName("org.apache.poi.ss.formula.eval.FunctionEval").getDeclaredField("functions");
_functions.setAccessible(true);
org.apache.poi.ss.formula.functions.Function[] functions = (org.apache.poi.ss.formula.functions.Function[])_functions.get(null);
functions[pos] = function;
}
public static void main(String[] args) throws Exception {
prepareFunctionEval(8, new RowFuncArrayReady());
Workbook workbook = WorkbookFactory.create(new FileInputStream("./ExcelUsingRowFormulaInArrayContext.xlsx"));
FormulaEvaluator evaluator = workbook.getCreationHelper().createFormulaEvaluator();
evaluator.setDebugEvaluationOutputForNextEval(true);
Sheet sheet = workbook.getSheetAt(0);
for (Row row : sheet) {
for (Cell cell : row) {
if (CellType.FORMULA == cell.getCellType()) {
System.out.println(cell.getCellFormula());
CellValue cellValue = evaluator.evaluate(cell);
System.out.println(cellValue);
}
}
}
workbook.close();
}
}
我的ExcelUsingRowFormulaInArrayContext.xlsx
看起来是这样的:
注意,公式{=IF(COUNTIF($J$6:$J$62,"?*")<ROW(J6)-5,"",INDEX(J:J,SMALL(IF(J$6:J$62<>"",ROW(J$6:J$62)),ROWS(J$6:J6))))}
是使用CtrlShiftEnter.输入的数组公式Apache POI无法判断Excel 365的新动态数组公式和溢出数组行为.
然后我的ExcelEvaluateROWFormulaAsArray
会打印出来:
IF(COUNTIF($J$6:$J$62,"?*")<ROW(J6)-5,"",INDEX(J:J,SMALL(IF(J$6:J$62<>"",ROW(J$6:J$62)),ROWS(J$6:J6))))
org.apache.poi.ss.usermodel.CellValue ["Text 1"]
IF(COUNTIF($J$6:$J$62,"?*")<ROW(K6)-5,"",INDEX(K:K,SMALL(IF(K$6:K$62<>"",ROW(K$6:K$62)),ROWS(K$6:K6))))
org.apache.poi.ss.usermodel.CellValue [1.0]
IF(COUNTIF($J$6:$J$62,"?*")<ROW(J7)-5,"",INDEX(J:J,SMALL(IF(J$6:J$62<>"",ROW(J$6:J$62)),ROWS(J$6:J7))))
org.apache.poi.ss.usermodel.CellValue ["Text 2"]
IF(COUNTIF($J$6:$J$62,"?*")<ROW(K7)-5,"",INDEX(K:K,SMALL(IF(K$6:K$62<>"",ROW(K$6:K$62)),ROWS(K$6:K7))))
org.apache.poi.ss.usermodel.CellValue [2.0]
IF(COUNTIF($J$6:$J$62,"?*")<ROW(J8)-5,"",INDEX(J:J,SMALL(IF(J$6:J$62<>"",ROW(J$6:J$62)),ROWS(J$6:J8))))
org.apache.poi.ss.usermodel.CellValue ["Text 3"]
IF(COUNTIF($J$6:$J$62,"?*")<ROW(K8)-5,"",INDEX(K:K,SMALL(IF(K$6:K$62<>"",ROW(K$6:K$62)),ROWS(K$6:K8))))
org.apache.poi.ss.usermodel.CellValue [3.0]
IF(COUNTIF($J$6:$J$62,"?*")<ROW(J9)-5,"",INDEX(J:J,SMALL(IF(J$6:J$62<>"",ROW(J$6:J$62)),ROWS(J$6:J9))))
org.apache.poi.ss.usermodel.CellValue ["Text 4"]
IF(COUNTIF($J$6:$J$62,"?*")<ROW(K9)-5,"",INDEX(K:K,SMALL(IF(K$6:K$62<>"",ROW(K$6:K$62)),ROWS(K$6:K9))))
org.apache.poi.ss.usermodel.CellValue [4.0]
IF(COUNTIF($J$6:$J$62,"?*")<ROW(J10)-5,"",INDEX(J:J,SMALL(IF(J$6:J$62<>"",ROW(J$6:J$62)),ROWS(J$6:J10))))
org.apache.poi.ss.usermodel.CellValue ["Text 5"]
IF(COUNTIF($J$6:$J$62,"?*")<ROW(K10)-5,"",INDEX(K:K,SMALL(IF(K$6:K$62<>"",ROW(K$6:K$62)),ROWS(K$6:K10))))
org.apache.poi.ss.usermodel.CellValue [5.0]
IF(COUNTIF($J$6:$J$62,"?*")<ROW(J11)-5,"",INDEX(J:J,SMALL(IF(J$6:J$62<>"",ROW(J$6:J$62)),ROWS(J$6:J11))))
org.apache.poi.ss.usermodel.CellValue [""]
IF(COUNTIF($J$6:$J$62,"?*")<ROW(K11)-5,"",INDEX(K:K,SMALL(IF(K$6:K$62<>"",ROW(K$6:K$62)),ROWS(K$6:K11))))
org.apache.poi.ss.usermodel.CellValue [""]
IF(COUNTIF($J$6:$J$62,"?*")<ROW(J12)-5,"",INDEX(J:J,SMALL(IF(J$6:J$62<>"",ROW(J$6:J$62)),ROWS(J$6:J12))))
org.apache.poi.ss.usermodel.CellValue [""]
IF(COUNTIF($J$6:$J$62,"?*")<ROW(K12)-5,"",INDEX(K:K,SMALL(IF(K$6:K$62<>"",ROW(K$6:K$62)),ROWS(K$6:K12))))
org.apache.poi.ss.usermodel.CellValue [""]
这与Excel的判断结果相同.
要判断Excel函数的哪些ApachePOI Java函数表示可以在数组上下文中使用,除了查看源代码之外别无 Select .所有这样的代码都在https://svn.apache.org/viewvc/poi/tags/REL_5_2_4/poi/src/main/java/org/apache/poi/ss/formula/及其子目录中.命名函数位于/Functions或/ATP子目录中.
但操作数有时也需要ArrayFunction
.大多数操作数都在/ev子目录中.例如,UnaryPlusEval
是数组上下文就绪的.因此+A1:A10
将在数组上下文中工作.但ConcatEval
并非如此.因此A1:A10&B1:B10
将不能在数组上下文中工作.
但也有一些函数,其中数组上下文中的函数根本没有记录在某个地方.例如,对于COUNTIF function,如果在数组上下文中像COUNTIF($B$69:B69, $D$6:$D$62)
一样使用,将会发生什么情况是不清楚的.如何处理What do you want to look for?
中的数组?微软没有透露任何关于这方面的信息.因此,我们所能做的就是判断Excel在这种情况下做了什么,然后try 使用Java来编程Excel的行为.这是非常具有挑战性的,而且容易出错.因此,我怀疑会有人这么做.我怀疑即使是微软也不知道Excel用户发现了什么有趣的公式解决方案,特别是在使用数组上下文的情况下.因此,如果有人需要那些有趣的公式解决方案,那么这个解决方案应该使用真正的Excel应用程序.