I want to copy Bloomberg BDH behavior.
BDH makes a web request and write an array (but doesn’t return an array style). During this web request, the function returns “#N/A Requesting”.
When the web request finished, the BDH() function writes the array result in the worksheet.
For example, in ExcelDNA, I succeed to write in the worksheet with a thread.
The result if you use the code below in a DNA file, the result of
=WriteArray(2;2)
will be
Line 1 > #N/A Requesting Data (0,1)
Line 2 > (1,0) (1,1)
The last issue is to replace #N/A Requesting Data with the value and copy the formula.
When you uncomment //xlActiveCellType.InvokeMember(“FormulaR1C1Local”, you are near the result but you don’t have the right behavior
File .dna
<DnaLibrary Language="CS" RuntimeVersion="v4.0">
<![CDATA[
using System;
using System.Collections.Generic;
using System.Reflection;
using System.Runtime.InteropServices;
using System.Threading;
using ExcelDna.Integration;
public static class WriteForXL
{
public static object[,] MakeArray(int rows, int columns)
{
if (rows == 0 && columns == 0)
{
rows = 1;
columns = 1;
}
object[,] result = new string[rows, columns];
for (int i = 0; i < rows; i++)
{
for (int j = 0; j < columns; j++)
{
result[i, j] = string.Format("({0},{1})", i, j);
}
}
return result;
}
public static object WriteArray(int rows, int columns)
{
if (ExcelDnaUtil.IsInFunctionWizard())
return "Waiting for click on wizard ok button to calculate.";
object[,] result = MakeArray(rows, columns);
var xlApp = ExcelDnaUtil.Application;
Type xlAppType = xlApp.GetType();
object caller = xlAppType.InvokeMember("ActiveCell", BindingFlags.GetProperty, null, xlApp, null);
object formula = xlAppType.InvokeMember("FormulaR1C1Local", BindingFlags.GetProperty, null, caller, null);
ObjectForThread q = new ObjectForThread() { xlRef = caller, value = result, FormulaR1C1Local = formula };
Thread t = new Thread(WriteFromThread);
t.Start(q);
return "#N/A Requesting Data";
}
private static void WriteFromThread(Object o)
{
ObjectForThread q = (ObjectForThread) o;
Type xlActiveCellType = q.xlRef.GetType();
try
{
for (int i = 0; i < q.value.GetLength(0); i++)
{
for (int j = 0; j < q.value.GetLength(1); j++)
{
if (i == 0 && j == 0)
continue;
Object cellBelow = xlActiveCellType.InvokeMember("Offset", BindingFlags.GetProperty, null, q.xlRef, new object[] { i, j });
xlActiveCellType.InvokeMember("Value", BindingFlags.SetProperty, null, cellBelow, new[] { Type.Missing, q.value[i, j] });
}
}
}
catch(Exception e)
{
}
finally
{
//xlActiveCellType.InvokeMember("Value", BindingFlags.SetProperty, null, q.xlRef, new[] { Type.Missing, q.value[0, 0] });
//xlActiveCellType.InvokeMember("FormulaR1C1Local", BindingFlags.SetProperty, null, q.xlRef, new [] { q.FormulaR1C1Local });
}
}
public class ObjectForThread
{
public object xlRef { get; set; }
public object[,] value { get; set; }
public object FormulaR1C1Local { get; set; }
}
}
]]>
</DnaLibrary>
@To Govert
BDH has become a standard in finance industry. People do not know how to manipulate an array (even the Ctrl+Shift+Enter).
BDH is the function that made Bloomberg so popular (to the disadvantage of Reuters).
However I will think of using your method or RTD.
Thanks for all your work in Excel DNA
My issue was :
writing dynamic array
data are retrieved asynchronous via a webservice
After discussing with Govert, I chose to take a result as an array and not to copy Bloomberg functions (write an array but return a single value).
Finally, to solve my issue, I used http://excel-dna.net/2011/01/30/resizing-excel-udf-result-arrays/
and reshape the
resize()function.This code is not RTD.
The code belows works in a .dna file