feat: support user defined numFmtId to numFmtCode mapping

cell.go

@@ -1350,6 +1350,10 @@ func (f *File) formattedValue(c *xlsxC, raw bool, cellType CellType) (string, er
 	if wb != nil && wb.WorkbookPr != nil {
 		date1904 = wb.WorkbookPr.Date1904
 	}
+	numFmtCode, ok := runNumFmtIdToCodeHook(f, numFmtID)
+	if ok {
+		return format(c.V, numFmtCode, date1904, cellType), err
+	}
 	if ok := builtInNumFmtFunc[numFmtID]; ok != nil {
 		return ok(c.V, builtInNumFmt[numFmtID], date1904, cellType), err
 	}

cell_test.go

@@ -894,6 +894,75 @@ func TestFormattedValue(t *testing.T) {
 	}
 }
 
+func TestFormattedValueWithWpsFile(t *testing.T) {
+
+	testWpsIdCodeMap := map[int]string{
+		14: "yyyy/m/d",
+		31: "yyyy\"年\"m\"月\"d\"日\"",
+	}
+
+	testWpsIdCodeMapHook := func(info NumFmtIdToCodeHookInfo, numFmtId int) (code string, ok bool) {
+		isWps := false
+	allAttrs:
+		for _, attrs := range info.XmlAttr {
+			for _, attr := range attrs {
+				if strings.Contains(attr.Value, "wps") {
+					isWps = true
+					break allAttrs
+				}
+			}
+		}
+		if !isWps {
+			return
+		}
+		code, ok = testWpsIdCodeMap[numFmtId]
+		return
+	}
+
+	testCases := []struct {
+		name             string
+		cellName         string
+		v                string
+		numFmtIdCodeHook NumFmtIdToCodeHook
+	}{
+		{
+			name:     "yy/m/d cell",
+			cellName: "A1",
+			v:        "23/1/1",
+		},
+		{
+			name:     "yyyy/m/d cell",
+			cellName: "A2",
+			v:        "01-01-23",
+		},
+		{
+			name:             "yyyy/m/d cell has hook",
+			cellName:         "A2",
+			v:                "2023/1/1",
+			numFmtIdCodeHook: testWpsIdCodeMapHook,
+		},
+		{
+			name:             "yyyy\"年\"m\"月\"d\"日\" cell",
+			cellName:         "A3",
+			v:                "2023年1月1日",
+			numFmtIdCodeHook: testWpsIdCodeMapHook,
+		},
+	}
+	for _, testCase := range testCases {
+		t.Run(testCase.name, func(t *testing.T) {
+			f, err := OpenFile(filepath.Join("test", "NumFmtCases.xlsx"), Options{
+				NumFmtIdToCodeHook: testCase.numFmtIdCodeHook,
+			})
+			if !assert.NoError(t, err) {
+				t.FailNow()
+			}
+			val, err := f.GetCellValue("Sheet1", testCase.cellName)
+			assert.NoError(t, err)
+			assert.Equal(t, testCase.v, val)
+		})
+	}
+}
+
 func TestFormattedValueNilXfs(t *testing.T) {
 	// Set the CellXfs to nil and verify that the formattedValue function does not crash
 	f := NewFile()

excelize.go

@@ -79,12 +79,16 @@ type charsetTranscoderFn func(charset string, input io.Reader) (rdr io.Reader, e
 // temporary directory when the file size is over this value, this value
 // should be less than or equal to UnzipSizeLimit, the default value is
 // 16MB.
+//
+// NumFmtIdToCodeHook User-defined mapping function for numFmtId to numFmtCode
+// if NumFmtIdToCodeHook function is nil will use default mapping
 type Options struct {
-	MaxCalcIterations uint
-	Password          string
-	RawCellValue      bool
-	UnzipSizeLimit    int64
-	UnzipXMLSizeLimit int64
+	MaxCalcIterations  uint
+	Password           string
+	RawCellValue       bool
+	UnzipSizeLimit     int64
+	UnzipXMLSizeLimit  int64
+	NumFmtIdToCodeHook NumFmtIdToCodeHook
 }
 
 // OpenFile take the name of an spreadsheet file and returns a populated

hooks.go

@@ -0,0 +1,23 @@
+package excelize
+
+import "encoding/xml"
+
+type NumFmtIdToCodeHookInfo struct {
+	XmlAttr map[string][]xml.Attr
+	NumFmt  []*xlsxNumFmt
+}
+
+// NumFmtIdToCodeHook User-defined mapping function for numFmtId to numFmtCode
+// if return ok is false, will use default mapping
+type NumFmtIdToCodeHook func(info NumFmtIdToCodeHookInfo, numFmtId int) (numFmtCode string, ok bool)
+
+func runNumFmtIdToCodeHook(file *File, numFmtId int) (numFmtCode string, ok bool) {
+	if file == nil || file.options == nil || file.options.NumFmtIdToCodeHook == nil {
+		return
+	}
+	hookInfo := NumFmtIdToCodeHookInfo{XmlAttr: file.xmlAttr}
+	if file.Styles != nil && file.Styles.NumFmts != nil {
+		hookInfo.NumFmt = file.Styles.NumFmts.NumFmt
+	}
+	return file.options.NumFmtIdToCodeHook(hookInfo, numFmtId)
+}