UG documentation 1014444: FAQ for How do I check if a formula in a cell contains an error value, and how do I retrieve what that error is?

Document-Processing-toc.html

@@ -6772,6 +6772,9 @@
                   <li>
 										<a href="/document-processing/excel/excel-library/net/faqs/how-to-merge-cells-preserving-topleft-value-and-format-in-xlsio">How to merge cells preserving topleft value and format in XlsIO?</a>
 									</li>
+									<li>
+										<a href="/document-processing/excel/excel-library/net/faqs/how-to-check-if-a-formula-in-a-cell-contains-an-error-value">How to check if a formula in a cell contains an error value?</a>
+									</li>
 								</ul>
 							</li>
 						</ul>

Document-Processing/Excel/Excel-Library/NET/faqs/how-to-check-if-a-formula-in-a-cell-contains-an-error-value.md

@@ -0,0 +1,103 @@
+---
+title: How to Check Formula Error Values in a Cell | Syncfusion
+description: Explains how to detect whether a formula returns an error using HasFormulaErrorValue and read the FormulaErrorValue via IRange in XlsIO.
+platform: document-processing
+control: XlsIO
+documentation: UG
+---
+
+# How to check if a formula in a cell contains an error value?
+
+In XlsIO there is no direct property that predicts whether a formula will evaluate to an error at design time, but the `IRange` interface exposes two useful members:
+
+- `HasFormulaErrorValue` (Read-Only): returns true when the formula in the cell evaluates to an error value.
+- `FormulaErrorValue` (Read-Only): returns the error value as a string (for example `#DIV/0!`, `#N/A`, etc.).
+
+The example below shows how to iterate the used range of a worksheet, check each cell for `HasFormulaErrorValue`, and print the `FormulaErrorValue` and the cell address.
+
+{% tabs %}
+{% highlight c# tabtitle="C# [Cross-platform]" %}
+using (ExcelEngine excelEngine = new ExcelEngine())
+{
+    IApplication application = excelEngine.Excel;
+    application.DefaultVersion = ExcelVersion.Xlsx;
+    IWorkbook workbook = application.Workbooks.Open(Path.GetFullPath(@"Input/InputTemplate.xlsx"));
+    IWorksheet worksheet = workbook.Worksheets[0];
+
+    IRange usedRange = worksheet.UsedRange;
+    int firstrow = usedRange.Row;
+    int lastrow = usedRange.LastRow;
+    int firstcol = usedRange.Column;
+    int lastcol = usedRange.LastColumn;
+
+    for (int row = firstrow; row <= lastrow; row++)
+    {
+        for (int col = firstcol; col <= lastcol; col++)
+        {
+            if (worksheet[row, col] != null && worksheet[row, col].HasFormulaErrorValue)
+            {
+                Console.WriteLine($"Formula error value: {worksheet[row,col].FormulaErrorValue} in Address: {worksheet[row,col].AddressLocal}");
+            }
+        }
+    }
+
+    workbook.SaveAs(Path.GetFullPath(@"Output/Output.xlsx"));
+}
+{% endhighlight %}
+
+{% highlight c# tabtitle="C# [Windows-specific]" %}
+using (ExcelEngine excelEngine = new ExcelEngine())
+{
+    IApplication application = excelEngine.Excel;
+    application.DefaultVersion = ExcelVersion.Xlsx;
+    IWorkbook workbook = application.Workbooks.Open("InputTemplate.xlsx");
+    IWorksheet worksheet = workbook.Worksheets[0];
+
+    IRange usedRange = worksheet.UsedRange;
+    int firstrow = usedRange.Row;
+    int lastrow = usedRange.LastRow;
+    int firstcol = usedRange.Column;
+    int lastcol = usedRange.LastColumn;
+
+    for (int row = firstrow; row <= lastrow; row++)
+    {
+        for (int col = firstcol; col <= lastcol; col++)
+        {
+            if (worksheet[row, col] != null && worksheet[row, col].HasFormulaErrorValue)
+            {
+                Console.WriteLine($"Formula error value: {worksheet[row,col].FormulaErrorValue} in Address: {worksheet[row,col].AddressLocal}");
+            }
+        }
+    }
+
+    workbook.SaveAs("Output.xlsx");
+}
+{% endhighlight %}
+
+{% highlight vb.net tabtitle="VB.NET [Windows-specific]" %}
+Using excelEngine As New ExcelEngine()
+    Dim application As IApplication = excelEngine.Excel
+    application.DefaultVersion = ExcelVersion.Xlsx
+    Dim workbook As IWorkbook = application.Workbooks.Open("InputTemplate.xlsx")
+    Dim worksheet As IWorksheet = workbook.Worksheets(0)
+
+    Dim usedRange As IRange = worksheet.UsedRange
+    Dim firstrow As Integer = usedRange.Row
+    Dim lastrow As Integer = usedRange.LastRow
+    Dim firstcol As Integer = usedRange.Column
+    Dim lastcol As Integer = usedRange.LastColumn
+
+    For row As Integer = firstrow To lastrow
+        For col As Integer = firstcol To lastcol
+            If worksheet(row, col) IsNot Nothing AndAlso worksheet(row, col).HasFormulaErrorValue Then
+                Console.WriteLine("Formula error value: " & worksheet(row, col).FormulaErrorValue & " in Address: " & worksheet(row, col).AddressLocal)
+            End If
+        Next
+    Next
+
+    workbook.SaveAs("Output.xlsx")
+End Using
+{% endhighlight %}
+{% endtabs %}
+
+A complete working example in C# is present on <a href="https://github.com/SyncfusionExamples/XlsIO-Examples/tree/1014444-FormulaError/FAQ/FormulaError%20Value/.NET/FormulaError%20Value">this GitHub page</a>.