resolve the issue corrupted xlsx after deleting formula of cell, reference #346

1 files changed, 55 insertions, 0 deletions

diff --git a/calcchain.go b/calcchain.go
new file mode 100644
index 0000000..285a3e9
--- /dev/null
+++ b/calcchain.go
@@ -0,0 +1,55 @@
+// Copyright 2016 - 2019 The excelize Authors. All rights reserved. Use of
+// this source code is governed by a BSD-style license that can be found in
+// the LICENSE file.
+//
+// Package excelize providing a set of functions that allow you to write to
+// and read from XLSX files. Support reads and writes XLSX file generated by
+// Microsoft Excel™ 2007 and later. Support save file without losing original
+// charts of XLSX. This library needs Go version 1.8 or later.
+
+package excelize
+
+import "encoding/xml"
+
+// calcChainReader provides a function to get the pointer to the structure
+// after deserialization of xl/calcChain.xml.
+func (f *File) calcChainReader() *xlsxCalcChain {
+	if f.CalcChain == nil {
+		var c xlsxCalcChain
+		_ = xml.Unmarshal(namespaceStrictToTransitional(f.readXML("xl/calcChain.xml")), &c)
+		f.CalcChain = &c
+	}
+	return f.CalcChain
+}
+
+// calcChainWriter provides a function to save xl/calcChain.xml after
+// serialize structure.
+func (f *File) calcChainWriter() {
+	if f.CalcChain != nil {
+		output, _ := xml.Marshal(f.CalcChain)
+		f.saveFileList("xl/calcChain.xml", output)
+	}
+}
+
+// deleteCalcChain provides a function to remove cell reference on the
+// calculation chain.
+func (f *File) deleteCalcChain(axis string) {
+	calc := f.calcChainReader()
+	if calc != nil {
+		for i, c := range calc.C {
+			if c.R == axis {
+				calc.C = append(calc.C[:i], calc.C[i+1:]...)
+			}
+		}
+	}
+	if len(calc.C) == 0 {
+		f.CalcChain = nil
+		delete(f.XLSX, "xl/calcChain.xml")
+		content := f.contentTypesReader()
+		for k, v := range content.Overrides {
+			if v.PartName == "/xl/calcChain.xml" {
+				content.Overrides = append(content.Overrides[:k], content.Overrides[k+1:]...)
+			}
+		}
+	}
+}