How to read single Excel cell value

using Microsoft.Office.Interop.Excel;

string path = "C:\\Projects\\ExcelSingleValue\\Test.xlsx ";

Application excel = new Application();
Workbook wb = excel.Workbooks.Open(path);
Worksheet excelSheet = wb.ActiveSheet;

//Read the first cell
string test = excelSheet.Cells[1, 1].Value.ToString();

wb.Close();

This example used the 'Microsoft Excel 15.0 Object Library' but may be compatible with earlier versions of Interop and other libraries.

You need to cast it to a string (not an array of string) since it's a single value.

var cellValue = (string)(excelWorksheet.Cells[10, 2] as Excel.Range).Value;

 //THIS IS WORKING CODE                        
 Microsoft.Office.Interop.Excel.Range Range_Number,r2;
 Range_Number = wsheet.UsedRange.Find("smth");
 string f_number="";

 r2 = wsheet.Cells;

 int n_c = Range_Number.Column;
 int n_r = Range_Number.Row;
 var number = ((Range)r2[n_r + 1, n_c]).Value;

 f_number = (string)number;