Assigning an icon to certain file types?

Hi,
Many programs give their own icon to certain file types in windows when you install them. As an example of this: When you install Microsoft Word it’s that programs icon that is used for files with the *.doc format. Can anybody tell me how I can do this with VB? I have a feeling it’s going to be an API call but because I’m not sure I’ve posted in the general section of this forum. Thanks

The file associations are stored in the Registry, under HKEY_CLASSES_ROOT. If you look under there, you will see loads of values for previously installed programs. Dissect those, and you'll see how to put an icon in. To register your own icon, simply add a registry key. For code to use the registry, go here: http://www.parksie.uklinux.net/registry.zip

Thanks Parksie!

Code for a Module

Code:

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Declare Function RegCloseKey Lib "advapi32.dll" (ByVal HKEY As Long) As Long
Declare Function RegCreateKey Lib "advapi32.dll" Alias "RegCreateKeyA" (ByVal HKEY As Long, ByVal lpSubKey As String, phkResult As Long) As Long
Declare Function RegDeleteKey Lib "advapi32.dll" Alias "RegDeleteKeyA" (ByVal HKEY As Long, ByVal lpSubKey As String) As Long
Declare Function RegDeleteValue Lib "advapi32.dll" Alias "RegDeleteValueA" (ByVal HKEY As Long, ByVal lpValueName As String) As Long
Declare Function RegOpenKey Lib "advapi32.dll" Alias "RegOpenKeyA" (ByVal HKEY As Long, ByVal lpSubKey As String, phkResult As Long) As Long
Declare Function RegQueryValueEx Lib "advapi32.dll" Alias "RegQueryValueExA" (ByVal HKEY As Long, ByVal lpValueName As String, ByVal lpReserved As Long, lpType As Long, lpData As Any, lpcbData As Long) As Long
Declare Function RegSetValueEx Lib "advapi32.dll" Alias "RegSetValueExA" (ByVal HKEY As Long, ByVal lpValueName As String, ByVal Reserved As Long, ByVal dwType As Long, lpData As Any, ByVal cbData As Long) As Long

Public Const HKEY_CLASSES_ROOT = &H80000000
Public Const HKEY_CURRENT_USER = &H80000001
Public Const HKEY_LOCAL_MACHINE = &H80000002
Public Const HKEY_USERS = &H80000003
Public Const HKEY_PERFORMANCE_DATA = &H80000004
Public Const REG_SZ = 1

Function RegQueryStringValue(ByVal HKEY As Long, ByVal strValueName As String)
    Dim lResult As Long
    Dim lValueType As Long
    Dim strBuf As String
    Dim lDataBufSize As Long
   
    On Error GoTo 0
    lResult = RegQueryValueEx(HKEY, strValueName, 0&, lValueType, ByVal 0&, lDataBufSize)
    If lResult = ERROR_SUCCESS Then
        If lValueType = REG_SZ Then
            strBuf = String(lDataBufSize, " ")
            lResult = RegQueryValueEx(HKEY, strValueName, 0&, 0&, ByVal strBuf, lDataBufSize)
            If lResult = ERROR_SUCCESS Then
                RegQueryStringValue = StripTerminator(strBuf)
            End If
        End If
    End If
End Function

Public Function GetSettingEx(HKEY As Long, sPath As String, sValue As String)
    Dim KeyHand&
    Dim datatype&
    Call RegOpenKey(HKEY, sPath, KeyHand&)
    GetSettingEx = RegQueryStringValue(KeyHand&, sValue)
    Call RegCloseKey(KeyHand&)
End Function

Function StripTerminator(ByVal strString As String) As String
    Dim intZeroPos As Integer

    intZeroPos = InStr(strString, Chr$(0))
    If intZeroPos > 0 Then
        StripTerminator = Left$(strString, intZeroPos - 1)
    Else
        StripTerminator = strString
    End If
End Function

Public Sub SaveSettingEx(HKEY As Long, sPath As String, sValue As String, sData As String)
    Dim KeyHand As Long
    Call RegCreateKey(HKEY, sPath, KeyHand)
    Call RegSetValueEx(KeyHand&, sValue, 0, REG_SZ, ByVal sData, Len(sData))
    Call RegCloseKey(KeyHand&)
End Sub

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Code for a CommandButton

Code:

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Private Sub Command1_Click()
    'Save a Value to the Registry
    SaveSettingEx HKEY_CLASSES_ROOT, "MyApp\DefaultIcon", "", "C:\MyIcon.ico"
End Sub

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Thanks to you also Megatron. I do know how to use the Registry APIs but when it's done for you it's a bonus. I'm thinking of creating a Registry OCX for personal use.