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updated the c# struct definition and add function call
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votaroe
votaroe
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Update:

I have updated the c# mapping with the feedback to look like this:

[StructLayout(LayoutKind.Sequential, CharSet = CharSet.Ansi)] 
public struct TMPData 
{             
    [MarshalAs(UnmanagedType.ByValTStr, SizeConst = 41)] 
    public string Lastname; 
    [MarshalAs(UnmanagedType.ByValTStr, SizeConst = 41)] 
    public string Firstname; 
    [MarshalAs(UnmanagedType.R8)] 
    public double Birthday; 
    [MarshalAs(UnmanagedType.ByValTStr, SizeConst = 17)] 
    public string Pid; 
    [MarshalAs(UnmanagedType.ByValTStr, SizeConst = 21)] 
    public string Title; 
    [MarshalAs(UnmanagedType.Bool)] 
    public bool Female; 
    [MarshalAs(UnmanagedType.ByValTStr, SizeConst = 41)] 
    public string Street; 
    [MarshalAs(UnmanagedType.ByValTStr, SizeConst = 11)] 
    public string ZipCode; 
    [MarshalAs(UnmanagedType.ByValTStr, SizeConst = 41)] 
    public string City; 
    [MarshalAs(UnmanagedType.ByValTStr, SizeConst = 21)] 
    public string Phone; 
    [MarshalAs(UnmanagedType.ByValTStr, SizeConst = 21)] 
    public string Fax; 
    [MarshalAs(UnmanagedType.ByValTStr, SizeConst = 21)] 
    public string Department; 
    [MarshalAs(UnmanagedType.ByValTStr, SizeConst = 21)] 
    public string Company; 
    [MarshalAs(UnmanagedType.ByValTStr, SizeConst = 41)] 
    public string Pn; 
    [MarshalAs(UnmanagedType.ByValTStr, SizeConst = 17)] 
    public string In; 
    [MarshalAs(UnmanagedType.ByValTStr, SizeConst = 9)] 
    public string Hi; 
    [MarshalAs(UnmanagedType.ByValTStr, SizeConst = 21)] 
    public string Account; 
    [MarshalAs(UnmanagedType.ByValTStr, SizeConst = 11)] 
    public string Valid; 
    [MarshalAs(UnmanagedType.ByValTStr, SizeConst = 11)] 
    public string Status; 
    [MarshalAs(UnmanagedType.ByValTStr, SizeConst = 21)] 
    public string Country; 
    [MarshalAs(UnmanagedType.ByValTStr, SizeConst = 21)] 
    public string NameAffix; 
    [MarshalAs(UnmanagedType.I4)] 
    public int W; 
    [MarshalAs(UnmanagedType.I4)] 
    public int H; 
    [MarshalAs(UnmanagedType.ByValTStr, SizeConst = 11)] 
    public string Bp; 
    [MarshalAs(UnmanagedType.ByValTStr, SizeConst = 10)] 
    public string SocialSecurityNumber; 
    [MarshalAs(UnmanagedType.ByValTStr, SizeConst = 3)] 
    public string State; 
}

The Init function:

[DllImport("MyDll.dll")] 
[return: MarshalAs(UnmanagedType.Bool)] 
public static extern bool Init(TMPData tmpData, int ErrorCode, bool ResetFatalError);

now fails with the following error:

"Attempted to read or write protected memory. This is often an indication that other memory is corrupt.

when I call it as shown below:

int errorCode = 0;
bool resetLastError = true;
TMPData tmpData = new TMPData();

        tmpData.Lastname = "TestLastName";
        tmpData.Firstname = "TestName";
        tmpData.Birthday = 28856.0;
        tmpData.Pid = "12345678";
        tmpData.Title = null;
        tmpData.Female = false;
        tmpData.Street = null; 
        tmpData.ZipCode = null;
        tmpData.City = null;
        tmpData.Phone = null;
        tmpData.Fax = null;
        tmpData.Department = null; 
        tmpData.Company = null;
        tmpData.Pn = null;
        tmpData.In = null;
        tmpData.Hi = null;
        tmpData.Account = null;
        tmpData.Valid = null;
        tmpData.Status = null;
        tmpData.Country = null;
        tmpData.NameAffix = null;
        tmpData.W = 0;
        tmpData.H = 0;
        tmpData.Bp = null;
        tmpData.SocialSecurityNumber = 0;
        tmpData.State = null;

bool success = Init(tmpData, errorCode, resetLastError);

If I change the ByValTStr to LPStr in the struct definition then the Init function succeeds but the GetData function returns incorrect string values. If I change LPStr back to ByValTStr the Init function fails but the GetData function returns the correct strings. I am not sure if I should marshal array[0..x] of char as LPStr of ByValTStr?

Update:

I have updated the c# mapping with the feedback to look like this:

[StructLayout(LayoutKind.Sequential, CharSet = CharSet.Ansi)] 
public struct TMPData 
{             
    [MarshalAs(UnmanagedType.ByValTStr, SizeConst = 41)] 
    public string Lastname; 
    [MarshalAs(UnmanagedType.ByValTStr, SizeConst = 41)] 
    public string Firstname; 
    [MarshalAs(UnmanagedType.R8)] 
    public double Birthday; 
    [MarshalAs(UnmanagedType.ByValTStr, SizeConst = 17)] 
    public string Pid; 
    [MarshalAs(UnmanagedType.ByValTStr, SizeConst = 21)] 
    public string Title; 
    [MarshalAs(UnmanagedType.Bool)] 
    public bool Female; 
    [MarshalAs(UnmanagedType.ByValTStr, SizeConst = 41)] 
    public string Street; 
    [MarshalAs(UnmanagedType.ByValTStr, SizeConst = 11)] 
    public string ZipCode; 
    [MarshalAs(UnmanagedType.ByValTStr, SizeConst = 41)] 
    public string City; 
    [MarshalAs(UnmanagedType.ByValTStr, SizeConst = 21)] 
    public string Phone; 
    [MarshalAs(UnmanagedType.ByValTStr, SizeConst = 21)] 
    public string Fax; 
    [MarshalAs(UnmanagedType.ByValTStr, SizeConst = 21)] 
    public string Department; 
    [MarshalAs(UnmanagedType.ByValTStr, SizeConst = 21)] 
    public string Company; 
    [MarshalAs(UnmanagedType.ByValTStr, SizeConst = 41)] 
    public string Pn; 
    [MarshalAs(UnmanagedType.ByValTStr, SizeConst = 17)] 
    public string In; 
    [MarshalAs(UnmanagedType.ByValTStr, SizeConst = 9)] 
    public string Hi; 
    [MarshalAs(UnmanagedType.ByValTStr, SizeConst = 21)] 
    public string Account; 
    [MarshalAs(UnmanagedType.ByValTStr, SizeConst = 11)] 
    public string Valid; 
    [MarshalAs(UnmanagedType.ByValTStr, SizeConst = 11)] 
    public string Status; 
    [MarshalAs(UnmanagedType.ByValTStr, SizeConst = 21)] 
    public string Country; 
    [MarshalAs(UnmanagedType.ByValTStr, SizeConst = 21)] 
    public string NameAffix; 
    [MarshalAs(UnmanagedType.I4)] 
    public int W; 
    [MarshalAs(UnmanagedType.I4)] 
    public int H; 
    [MarshalAs(UnmanagedType.ByValTStr, SizeConst = 11)] 
    public string Bp; 
    [MarshalAs(UnmanagedType.ByValTStr, SizeConst = 10)] 
    public string SocialSecurityNumber; 
    [MarshalAs(UnmanagedType.ByValTStr, SizeConst = 3)] 
    public string State; 
}

The Init function:

[DllImport("MyDll.dll")] 
[return: MarshalAs(UnmanagedType.Bool)] 
public static extern bool Init(TMPData tmpData, int ErrorCode, bool ResetFatalError);

now fails with the following error:

"Attempted to read or write protected memory. This is often an indication that other memory is corrupt.

when I call it as shown below:

int errorCode = 0;
bool resetLastError = true;
TMPData tmpData = new TMPData();

        tmpData.Lastname = "TestLastName";
        tmpData.Firstname = "TestName";
        tmpData.Birthday = 28856.0;
        tmpData.Pid = "12345678";
        tmpData.Title = null;
        tmpData.Female = false;
        tmpData.Street = null; 
        tmpData.ZipCode = null;
        tmpData.City = null;
        tmpData.Phone = null;
        tmpData.Fax = null;
        tmpData.Department = null; 
        tmpData.Company = null;
        tmpData.Pn = null;
        tmpData.In = null;
        tmpData.Hi = null;
        tmpData.Account = null;
        tmpData.Valid = null;
        tmpData.Status = null;
        tmpData.Country = null;
        tmpData.NameAffix = null;
        tmpData.W = 0;
        tmpData.H = 0;
        tmpData.Bp = null;
        tmpData.SocialSecurityNumber = 0;
        tmpData.State = null;

bool success = Init(tmpData, errorCode, resetLastError);

If I change the ByValTStr to LPStr in the struct definition then the Init function succeeds but the GetData function returns incorrect string values. If I change LPStr back to ByValTStr the Init function fails but the GetData function returns the correct strings. I am not sure if I should marshal array[0..x] of char as LPStr of ByValTStr?

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votaroe
votaroe
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calling delphi dll from c#

I have a Delphi dll defined like this:

TMPData = record
 Lastname, Firstname: array[0..40] of char;
 Birthday: TDateTime;
 Pid: array[0..16] of char;
 Title: array[0..20] of char;
 Female: Boolean;
 Street: array[0..40] of char;
 ZipCode: array[0..10] of char;
 City: array[0..40] of char;
 Phone, Fax, Department, Company: array[0..20] of char;
 Pn: array[0..40] of char;
 In: array[0..16] of char;
 Hi: array[0..8] of char;
 Account: array[0..20] of char;
 Valid, Status: array[0..10] of char;
 Country, NameAffix: array[0..20] of char;
 W, H: single;
 Bp: array[0..10] of char;
 SocialSecurityNumber: array[0..9] of char;
 State: array[0..2] of char;
end;   

function Init(const tmpData: TMPData; var ErrorCode: integer; ResetFatalError: boolean = false): boolean;

procedure GetData(out tmpData: TMPData);

My current c# signatures looks like this:

[StructLayout(LayoutKind.Sequential, CharSet = CharSet.Ansi)]
public struct TMPData
{            
    [MarshalAs(UnmanagedType.LPStr, SizeConst = 40)]
    public string Lastname;
    [MarshalAs(UnmanagedType.LPStr, SizeConst = 40)]
    public string Firstname;
    [MarshalAs(UnmanagedType.R8)]
    public double Birthday;
    [MarshalAs(UnmanagedType.LPStr, SizeConst = 16)]
    public string Pid;
    [MarshalAs(UnmanagedType.LPStr, SizeConst = 20)]
    public string Title;
    [MarshalAs(UnmanagedType.Bool)]
    public bool Female;
    [MarshalAs(UnmanagedType.LPStr, SizeConst = 40)]
    public string Street;
    [MarshalAs(UnmanagedType.LPStr, SizeConst = 10)]
    public string ZipCode;
    [MarshalAs(UnmanagedType.LPStr, SizeConst = 40)]
    public string City;
    [MarshalAs(UnmanagedType.LPStr, SizeConst = 20)]
    public string Phone;
    [MarshalAs(UnmanagedType.LPStr, SizeConst = 20)]
    public string Fax;
    [MarshalAs(UnmanagedType.LPStr, SizeConst = 20)]
    public string Department;
    [MarshalAs(UnmanagedType.LPStr, SizeConst = 20)]
    public string Company;
    [MarshalAs(UnmanagedType.LPStr, SizeConst = 40)]
    public string Pn;
    [MarshalAs(UnmanagedType.LPStr, SizeConst = 16)]
    public string In;
    [MarshalAs(UnmanagedType.LPStr, SizeConst = 8)]
    public string Hi;
    [MarshalAs(UnmanagedType.LPStr, SizeConst = 20)]
    public string Account;
    [MarshalAs(UnmanagedType.LPStr, SizeConst = 10)]
    public string Valid;
    [MarshalAs(UnmanagedType.LPStr, SizeConst = 10)]
    public string Status;
    [MarshalAs(UnmanagedType.LPStr, SizeConst = 20)]
    public string Country;
    [MarshalAs(UnmanagedType.LPStr, SizeConst = 20)]
    public string NameAffix;
    [MarshalAs(UnmanagedType.I4)]
    public int W;
    [MarshalAs(UnmanagedType.I4)]
    public int H;
    [MarshalAs(UnmanagedType.LPStr, SizeConst = 10)]
    public string Bp;
    [MarshalAs(UnmanagedType.LPStr, SizeConst = 9)]
    public string SocialSecurityNumber;
    [MarshalAs(UnmanagedType.LPStr, SizeConst = 2)]
    public string State;
}

[DllImport("MyDll.dll")]
[return: MarshalAs(UnmanagedType.Bool)]
public static extern bool Init(TMPData tmpData, int ErrorCode, bool ResetFatalError);

[DllImport("MyDll.dll")]
[return: MarshalAs(UnmanagedType.Bool)]
public static extern bool GetData(out TMPData tmpData);

I first call Init setting the BirthDay, LastName and FirstName. I then call GetData but the TMPData structure I get back is incorrect. The FirstName, LastName and Birthday fields are populated but the data is incorrect. Is the mapping correct? ( "array[0..40] of char" equal to "[MarshalAs(UnmanagedType.LPStr, SizeConst = 40)]" )?