C# Conditional Formatting on Microsoft.Office.Interop.Excel.Cells based on cell text

Question

I write a code with C# and Microsoft.Office.Interop.Excel . In generated a drop-down list where one can chose between "okay", "delete", "else". Now I want that the cell becomes red if "delete" is chosen. I tried to do this with Excel.FormatCondition :

Excel.FormatCondition condition = mysheet.get_Range("J2:J10",
    Type.Missing).FormatConditions.Add(Type:Excel.XlFormatConditionType.xlTextString,
    Operator: Excel.XlFormatConditionOperator.xlEqual, Formula1: "=\"delete\"");
condition.Interior.ColorIndex = 3;

With this code I get an error:

System.Runtime.InteropServices.COMException: 'Exception from HRESULT: 0x800A03EC'

Answer 1

Old question, but hopefully this might help someone else. When you set the type to Type:Excel.XlFormatConditionType.xlTextString , you need to set the String: and TextOperator: parameters and not Operator: and Formula1: as shown in the question.

Fixing the code:

FormatConditions.Add(Type:Excel.XlFormatConditionType.xlTextString,
    TextOperator: Excel.XlContainsOperator.xlContains, String: "delete");

Answer 2

I have found the solution. It is straight forward. I had to use XlFormatConditionType.xlCellValue instead of TextString:

//Drop-down List
var list = new System.Collections.Generic.List<string>();

list.Add("okay");
list.Add("delete");
list.Add("else (Comment)");
var flatList = string.Join(",", list.ToArray());

var celldd = (Excel.Range)mysheet.Cells[row_counter, 10];

celldd.Validation.Delete();
try
{
    int type = celldd.Validation.Type;
    Console.WriteLine("The validation have already been added");
}
catch (System.Runtime.InteropServices.COMException)
{
    celldd.Validation.Add(
    Excel.XlDVType.xlValidateList,
    Excel.XlDVAlertStyle.xlValidAlertInformation,
    Excel.XlFormatConditionOperator.xlBetween,
    flatList, misValue);
 }
 celldd.Validation.InCellDropdown = true;
 celldd.Validation.IgnoreBlank = true;
 celldd.Locked = false;

 celldd.Value2 = "Choose";
 celldd.Interior.Color = ColorTranslator.ToOle(Color.Plum);

 //Conditional Formatting
 Excel.FormatCondition condition1 = mysheet.get_Range("J2:J10",
        Type.Missing).FormatConditions.Add(Excel.XlFormatConditionType.xlCellValue, Excel.XlFormatConditionOperator.xlEqual, "=\"delete\"", misValue, misValue, misValue, misValue, misValue);
 condition1.Interior.ColorIndex = 3;  //red

 Excel.FormatCondition condition2 = mysheet.get_Range("J2:J10",
        Type.Missing).FormatConditions.Add(Excel.XlFormatConditionType.xlCellValue, Excel.XlFormatConditionOperator.xlEqual, "=\"okay\"", misValue, misValue, misValue, misValue, misValue);
 condition2.Interior.ColorIndex = 43; //green

Excel.FormatCondition condition3 = mysheet.get_Range("J2:J10",
        Type.Missing).FormatConditions.Add(Excel.XlFormatConditionType.xlCellValue, Excel.XlFormatConditionOperator.xlEqual, "=\"else (Comment)\"", misValue, misValue, misValue, misValue, misValue);
condition3.Interior.ColorIndex = 44;  //yellow