I want to search through existing Excel files with a macro, but I don't want to display those files when they're opened by the code. Is there a way to have them open "in the background", so to speak?
You can use a library called ExcelLibrary. It's a free, open source library posted on Google Code:
This looks to be a port of the PHP ExcelWriter that you mentioned above. It will not write to the new .xlsx format yet, but they are working on adding that functionality in.
It's very simple, small and easy to use. Plus it has a DataSetHelper that lets you use DataSets and DataTables to easily work with Excel data.
ExcelLibrary seems to still only work for the older Excel format (.xls files), but may be adding support in the future for newer 2007/2010 formats.
There are a few known bugs with each library as noted in the comments. In all, EPPlus seems to be the best choice as time goes on. It seems to be more actively updated and documented as well.
Also, as noted by @АртёмЦарионов below, EPPlus has support for Pivot Tables and ExcelLibrary may have some support (Pivot table issue in ExcelLibrary)
Here some example code for ExcelLibrary:
Here is an example taking data from a database and creating a workbook from it. Note that the ExcelLibrary code is the single line at the bottom:
//Create the data set and table DataSet ds = new DataSet("New_DataSet"); DataTable dt = new DataTable("New_DataTable"); //Set the locale for each ds.Locale = System.Threading.Thread.CurrentThread.CurrentCulture; dt.Locale = System.Threading.Thread.CurrentThread.CurrentCulture; //Open a DB connection (in this example with OleDB) OleDbConnection con = new OleDbConnection(dbConnectionString); con.Open(); //Create a query and fill the data table with the data from the DB string sql = "SELECT Whatever FROM MyDBTable;"; OleDbCommand cmd = new OleDbCommand(sql, con); OleDbDataAdapter adptr = new OleDbDataAdapter(); adptr.SelectCommand = cmd; adptr.Fill(dt); con.Close(); //Add the table to the data set ds.Tables.Add(dt); //Here's the easy part. Create the Excel worksheet from the data set ExcelLibrary.DataSetHelper.CreateWorkbook("MyExcelFile.xls", ds);
Creating the Excel file is as easy as that. You can also manually create Excel files, but the above functionality is what really impressed me.
You can try this direct
VBA approach which doesn't require HEX editing. It will work for any files (*.xls, *.xlsm, *.xlam ...).
Tested and works on:
Excel 2013 - 32 bit version
Excel 2016 - 32 bit version
Looking for 64 bit version? See this answer
How it works
I will try my best to explain how it works - please excuse my English.
- The VBE will call a system function to create the password dialog box.
- If user enters the right password and click OK, this function returns 1. If user enters the wrong password or click Cancel, this function returns 0.
- After the dialog box is closed, the VBE checks the returned value of the system function
- if this value is 1, the VBE will "think" that the password is right, hence the locked VBA project will be opened.
- The code below swaps the memory of the original function used to display the password dialog with a user defined function that will always return 1 when being called.
Using the code
Please backup your files first!
- Open the file(s) that contain your locked VBA Projects
Create a new xlsm file and store this code in Module1
code credited to Siwtom (nick name), a Vietnamese developer
Option Explicit Private Const PAGE_EXECUTE_READWRITE = &H40 Private Declare Sub MoveMemory Lib "kernel32" Alias "RtlMoveMemory" _ (Destination As Long, Source As Long, ByVal Length As Long) Private Declare Function VirtualProtect Lib "kernel32" (lpAddress As Long, _ ByVal dwSize As Long, ByVal flNewProtect As Long, lpflOldProtect As Long) As Long Private Declare Function GetModuleHandleA Lib "kernel32" (ByVal lpModuleName As String) As Long Private Declare Function GetProcAddress Lib "kernel32" (ByVal hModule As Long, _ ByVal lpProcName As String) As Long Private Declare Function DialogBoxParam Lib "user32" Alias "DialogBoxParamA" (ByVal hInstance As Long, _ ByVal pTemplateName As Long, ByVal hWndParent As Long, _ ByVal lpDialogFunc As Long, ByVal dwInitParam As Long) As Integer Dim HookBytes(0 To 5) As Byte Dim OriginBytes(0 To 5) As Byte Dim pFunc As Long Dim Flag As Boolean Private Function GetPtr(ByVal Value As Long) As Long GetPtr = Value End Function Public Sub RecoverBytes() If Flag Then MoveMemory ByVal pFunc, ByVal VarPtr(OriginBytes(0)), 6 End Sub Public Function Hook() As Boolean Dim TmpBytes(0 To 5) As Byte Dim p As Long Dim OriginProtect As Long Hook = False pFunc = GetProcAddress(GetModuleHandleA("user32.dll"), "DialogBoxParamA") If VirtualProtect(ByVal pFunc, 6, PAGE_EXECUTE_READWRITE, OriginProtect) <> 0 Then MoveMemory ByVal VarPtr(TmpBytes(0)), ByVal pFunc, 6 If TmpBytes(0) <> &H68 Then MoveMemory ByVal VarPtr(OriginBytes(0)), ByVal pFunc, 6 p = GetPtr(AddressOf MyDialogBoxParam) HookBytes(0) = &H68 MoveMemory ByVal VarPtr(HookBytes(1)), ByVal VarPtr(p), 4 HookBytes(5) = &HC3 MoveMemory ByVal pFunc, ByVal VarPtr(HookBytes(0)), 6 Flag = True Hook = True End If End If End Function Private Function MyDialogBoxParam(ByVal hInstance As Long, _ ByVal pTemplateName As Long, ByVal hWndParent As Long, _ ByVal lpDialogFunc As Long, ByVal dwInitParam As Long) As Integer If pTemplateName = 4070 Then MyDialogBoxParam = 1 Else RecoverBytes MyDialogBoxParam = DialogBoxParam(hInstance, pTemplateName, _ hWndParent, lpDialogFunc, dwInitParam) Hook End If End Function
Paste this code under the above code in Module1 and run it
Sub unprotected() If Hook Then MsgBox "VBA Project is unprotected!", vbInformation, "*****" End If End Sub
Come back to your VBA Projects and enjoy.
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