调用CryptCATCatalogInfoFromContext抛出错误

Question

我想将函数CryptCATCatalogInfoFromContext称为wintrust.dll中可用的函数。但是当我这样做时，我收到一个错误，它说指定的数组不是预期的类型。，我使用下面的代码来调用方法。我使用的某些数据类型似乎与所需的数据类型不匹配。

    'import wintrust.dll
    <DllImport("Wintrust.dll", PreserveSig:=True, SetLastError:=False)> _
    Private Shared Function CryptCATCatalogInfoFromContext(ByVal catalogContext As IntPtr, ByVal hash As CATALOG_INFO_, ByVal dwFlags As Integer) As Boolean
    End Function

    'create structure CATALOG_INFO
    <StructLayout(LayoutKind.Sequential)> _
        Public Structure CATALOG_INFO_
        Public cbStruct As UInteger
        <MarshalAs(UnmanagedType.SafeArray)> _
        Public wszCatalogFile() As Char 
    End Structure

我已经拿到CatalogContext了。

        Dim infoStruct As New CATALOG_INFO_()
        infoStruct.cbStruct = 256
        Dim c(255) As Char
        infoStruct.wszCatalogFile = c
        CryptCATCatalogInfoFromContext(CatalogContext, infoStruct, 0)

最后一行抛出错误指定的数组不是预期的类型。是否对数组使用了错误的数据类型？

Answer 1

是的，申报错误。它不是一个SafeArray，而是一个Unicode字符串。适当的声明是：

<StructLayout(LayoutKind.Sequential, CharSet:=CharSet.Unicode)> _
Public Structure CATALOG_INFO
    Public cbStruct As UInteger
    <MarshalAs(UnmanagedType.ByValTStr, SizeConst:=260)> _
    Public wszCatalogFile As String
End Structure