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  • PHP GD issues with ImageCreateTrueColor and PNGs

    - by DrPheltRight
    I am resizing PNG images using the GD image library function ImageCopyResampled(). It all works fine, I can even keep alpha blending transparency with the use of ImageCreateTrueColor() rather than using ImageCreate() to create the resized image. The problem is, that if I use ImageCreateTrueColor() rather than ImageCreate() the file size of PNG files increases from something like 80kb to 150kb. If I use ImageCreate() the file size stays around the same size, but colors screw! So my question is, how can I retain alpha blending when resizing PNG images without increasing the file size? Oh and I am reducing the dimensions of the PNGs.

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  • how to get the properties of a bitmap?

    - by BlueMonster
    How would i grab a bitmap's copyright date? I've been googling around for some pointers in the right direction, can't seem to find much though. Any ideas? private void toolStripMenuItemLoadImage_Click(object sender, EventArgs e) { using (OpenFileDialog ofd = new OpenFileDialog()) { ofd.Title = "Load Image"; if (ofd.ShowDialog() == DialogResult.OK) { firstLoaded = new Bitmap(ofd.FileName); String details = //Grab the copyright date of the image here; this.Invalidate(); } } isLoaded = true; }

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  • NoMethodError when using .where (eager fetching)

    - by Ethan Leroy
    I have the following model classes... class Image < ActiveRecord::Base attr_accessible :description, :title has_many :imageTags has_many :tags, :through => :imageTags end class Tag < ActiveRecord::Base attr_accessible :name has_many :imageTags has_many :images, :through => :imageTags end class ImageTag < ActiveRecord::Base attr_accessible :position belongs_to :image belongs_to :tag end And when I use find for getting the Tag with the id 1 t = Tag.find(1); @images = t.images; But when I do the same with where, I get a NoMethodError, with the description undefined method 'images': t = Tag.where(:name => "foo"); @images = t.images; I also tried adding .includes(:images) before the .where statement, but that doesn't work too. So, how can I get all Images that belong to a Tag?

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  • How to find the real problem line in my code with Application Verifier ?

    - by Newbie
    I am now trying to use this Application Verifier debugging tool, but i am stuck, first of all: it breaks the program at a line that is simple variable set line (s = 1; for example) Secondly, now when i run this program under debugger, my program seems to have changed its behaviour: i am drawing image, and now one of the colors has changed o_O, all those parts of the image that i dont draw on, has changed the color to #CDCDCD when it should be #000000, and i already set the default color to zero, still it becomes to #CDCDCD. How do i make any sense to this? Here is the output AV gave me: VERIFIER STOP 00000002: pid 0x8C0: Access violation exception. 14873000 : Invalid address causing the exception 004E422C : Code address executing the invalid access 0012EB08 : Exception record 0012EB24 : Context record AVRF: Noncontinuable verifier stop 00000002 encountered. Terminating process ... The program '[2240] test.exe: Native' has exited with code -1073741823 (0xc0000001).

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  • Animate css attributes: set "bottom" and remove "top"

    - by Slevin
    I'm working on a few animations with jQuery. I have 3-4 elements which should slide in from the top. I defined their positions with css: #element-1 { top:124px; left:0px; right:auto; bottom:auto; } #element-2 { top:230px; left:670px; right:auto; bottom:auto; } #element-3 { top:auto; left:0px; right:auto; bottom:100px; } Then I save their positions initial on pageload, cause i have to manipulate the css value to top: -1000px to hide them and make the "slide in from top" animation possible. var image_margins = []; $('img').each(function() { var obj = $(this), id = obj.attr('id'), mtop = obj.css('top'), mleft = obj.css('left'), mright = obj.css('right'), mbottom = obj.css('bottom'); // save alle margins in array image_margins[id] = {mtop:mtop,mleft:mleft,mright:mright,mbottom:mbottom}; // hide all content elements obj.css({'top':'-1000px'}); }); When the user clicks the animate button, the elements should slide to their saved positions. The problem: i can't remove the top attribute. Some elements only have bottom margins. I tried to set top to auto or '', but it's always 0px in DOM inspector. And bottom don't work if top is set. How can i get rid of the top attribute? $('.button').click(function(){ $('img').each(function() { var image = $(this), id = image.attr('id'), timeout = 0; setTimeout(function() { var mtop, mleft, mright, mbottom; if (image_margins[id].mtop != 'auto') { mtop = image_margins[id].mtop; } else { mtop = ''; } if (image_margins[id].mleft != 'auto') { mleft = image_margins[id].mleft; } else { mleft = ''; } if (image_margins[id].mright != 'auto') { mright = image_margins[id].mright; } else { mright = ''; } if (image_margins[id].mbottom != 'auto') { mbottom = image_margins[id].mbottom; } else { mbottom = ''; } image.animate({'top':mtop,'left':mleft,'right':mright,'bottom':mbottom},500); },timeout); timeout = timeout + 200; }); });

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  • Displaying a well formatted table

    - by user1378680
    Please take a look at the picture below. The header for the second column is displaying DISTRICT under SENATORIAL. But that's not the case for the 2nd and 3rd Rows under the 2nd Column. What I want to achieve is that words/strings should not ba able to extend width of the table.... The CSS I'm using is beneath. table { width: 650px; font-family: calibri; word-wrap: break-word; margin-left: 115px; } th { padding: 3px; color: white; text-transform: uppercase; font-size: 12px; background-image: url(navbg.png); font-weight: normal; word-wrap: break-word; font-family: "Trebuchet MS"; } Image:

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  • C#: Using regular expression (Regex) to duplicate a specific character in a string

    - by user3703944
    Anyone know how to use regex to duplicate a specific character in a string? I have a path that is entered like this: C:/Example/example I would like to use regex (or any other method) to display it like this: C://Example//example Is it possible? This is where I'm getting the file path private void btnSearchImage_Click_1(object sender, EventArgs e) { OpenFileDialog ofd = new OpenFileDialog(); ofd.Filter = "Image Files(*.jpg; *.jpeg; *.gif; *.bmp)|*.jpg; *.jpeg; *.gif; *.bmp"; if (ofd.ShowDialog() == System.Windows.Forms.DialogResult.OK) { string filenName = ofd.FileName; pictureBox1.Image = new Bitmap(filenName); string path = filenName; txtimgPath.Text = path; } } Thanks

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  • UI updates not happening in the expected order

    - by allonym
    I have a Panel which hosts a number of child controls in a grid layout. The child controls each consist of a Panel with a PictureBox and a Label. When one of these child controls is clicked it becomes "selected" (which basically entails changing its background to a different color) and an event is fired. In the handler for this event, an image is displayed in a PictureBox on a separate form. In code, the background of the child control is definitely changed before firing the event, but for some reason it never updates at runtime until after the image has updated in the other Form. I've tried to Invalidate() and Refresh() the child control before firing the event, without effect. Why is this happening, and what can I do to set it right?

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  • how to aggregate information on UIImage?

    - by user1582281
    I want to draw on each drawing cycle 1000 more lines on my UIIMage, right now I do it by : -(void)drawRect { for(int i=0;i<1000;i++) { UIGraphicsBeginImageContext(myImage.size); code to draw line on current context... draw previous info from myImage: [myImage drawInRect:myRect]; //store info from context back to myImage myImage=UIGraphicsGetImageFromCurrentImageContext(); UIGraphicsEndImageContext(); } //append the image on the right side of current context: [myImage drawInRect:myRightRect]; } problem is that I think that drawing entire image each time just for the few lines added is very expensive, anyone has any idea how to optimize it?

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  • jQuery: set the width of a textarea?

    - by AP257
    What it says on the tin: how do I set the width of a textarea in jQuery? I want to set the width of a textarea to match the width of a particular image. Using .width() works for setting the width of an image, but not of a textarea. $(document).ready(function() { var width = $("#my_image").width(); $("#another_image").width(width); // works $("#my_textarea").width(width); // fails }); How do I set the width of a textarea?

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  • How to detect if an element exists in Watir

    - by Rijksband
    Hi, I'm relatively new to Watir but can find no good documentation (examples) regarding how to check if an element exists. There are the API specs, of course, but these make precious little sense to me if I don't find an example. I've tried both combinations but nothing seems to work... if browser.image (:src "/media/images/icons/reviewertools/editreview.jpg").exists then... if browser.image (:src "/media/images/icons/reviewertools/editreview.jpg").exists? then... If anyone has a concrete suggestion as per how to implement this, please help! Thanks!

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  • Using Fancybox for country select in WordPress

    - by user2076774
    I am new to developing sites and just started using wordpress. I was told that I could use fancybox to help create a popup that would allow a person to select a country. Something similar to below, the only problem is I have no clue how to do this, I installed a fancybox plugin in (http://wordpress.org/plugins/fancybox-for-wordpress/). The way the person did it was you click on an image and then this text country pops up. How do I implement this to pop up a country select after you click on an image? Thanks!

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  • New line before header()

    - by MetalAdam
    I'm working with a custom made Joomla script that generates an image from a blob in a database. However, when we moved it from an Apache server to an IIS server, the script is breaking. Upon investigation, it seems that now, there is a line break that is getting appended before the header function is being run (when I comment out the image portion, and do an echo "test";, test gets printed on line 2 of the source code. I've gone through the script over and over again, and through the many files in the component, and can't seem to find out where this new line is coming from. At all. I've tried using ob_start() and many similar functions, but nothing seems to work. I'm completely out of ideas, and don't know where to turn. Is there a way to trace what files are being called in the page, perhaps? Any thoughts on further steps?

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  • Divs: Equal Horizontal Spacing

    - by Vecta
    I'm creating a site that has a series of four images on the homepage used as navigation with a large image beneath. <div style="width: 696px"> <div class="imglink"></div> <div class="imglink"></div> <div class="imglink"></div> <div class="imglink"></div> </div> <div style="width:696px"> ... </div> The "imglink" divs are 160px wide. I would like the images in the top div to be horizontally spaced evenly inside the div, with the two outer divs flush with the edges of the image below. I've been trying out floats, margins, padding, etc for a couple hours now and can't figure it out. Thanks for your help!

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  • How to get the number of files in a folder as a variable?

    - by Jason
    Using bash, how can one get the number of files in a folder, excluding directories from a shell script without the interpreter complaining? With the help of a friend, I've tried $files=$(find ../ -maxdepth 1 -type f | sort -n) $num=$("ls -l" | "grep ^-" | "wc -l") which returns from the command line: ../1-prefix_blended_fused.jpg: No such file or directory ls -l : command not found grep ^-: command not found wc -l: command not found respectively. These commands work on the command line, but NOT with a bash script. Given a file filled with image files formatted like 1-pano.jpg, I want to grab all the images in the directory to get the largest numbered file to tack onto the next image being processed. Why the discrepancy?

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  • Inconsistent behaviour from SDL_BlitSurface

    - by bardes
    Here is an example code: #include <SDL/SDL.h> #include <SDL/SDL_image.h> #include <stdio.h> int main() { if(SDL_Init(SDL_INIT_EVERYTHING) == -1) { printf("SDL ERROR: %s", SDL_GetError()); return 1; } SDL_Surface *screen; screen = SDL_SetVideoMode(128, 128, 32, SDL_SWSURFACE); SDL_Surface *img; img = IMG_Load("./debug.png"); SDL_BlitSurface(img, NULL, screen, NULL); SDL_Flip(screen); SDL_Delay(1000); SDL_FreeSurface(img); SDL_Quit(); return 0; } It compiles fine, but when I run it sometimes it works and most times only part of the image is displayed. I really can't imagine what's causing that... EDIT: This is the image I'm using to test the program: http://img140.imageshack.us/img140/3858/debugi.png

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  • Windows Backup fails with 0x80070002: "The system cannot find the file specified"

    - by James Johnston
    Windows 7 Backup is failing. When backing up even a single insignificant directory (e.g. I chose only the empty "Contacts" directory, leaving all other directories unchecked), I get this error within a few seconds and the backup fails. If I uncheck all files/directories, and just do the system image - then the system image is backed up OK without issue. Backup destination is an external USB hard drive. Steps to reproduce and subsequent failure: Set up backup to go to external hard drive. Don't back up system image. Back up "Contacts" directory only for my profile. Start backup. Immediately view the status of the backup, it stays on "Creating a shadow copy..." for a few seconds, and then the backup fails. Click Options button, and it says "Check your backup / The system cannot find the file specified." - with options to "Try to run backup again" or "Change backup settings". If I click "Show Details", then it says: Backup time: 4/12/2012 04:38 Backup location: My Book (D:) Error code: 0x80070002 An examination of the Event Log shows nothing useful beyond the following: Log Name: Application Source: Windows Backup Date: 4/12/2012 04:38:44 Event ID: 4104 Task Category: None Level: Error Keywords: Classic User: N/A Computer: JTJLaptop Description: The backup was not successful. The error is: The system cannot find the file specified. (0x80070002). Event Xml: <Event xmlns="http://schemas.microsoft.com/win/2004/08/events/event"> <System> <Provider Name="Windows Backup" /> <EventID Qualifiers="0">4104</EventID> <Level>2</Level> <Task>0</Task> <Keywords>0x80000000000000</Keywords> <TimeCreated SystemTime="2012-04-12T04:38:44.000000000Z" /> <EventRecordID>23979</EventRecordID> <Channel>Application</Channel> <Computer>JTJLaptop</Computer> <Security /> </System> <EventData> <Data>The system cannot find the file specified. (0x80070002)</Data> <Binary>02000780E30500003F0900005B090000420ED1665C2BEE174B64529CB14610EA71000000</Binary> </EventData> </Event> What I have tried: ChkDsk on both C: (main drive) and D: (backup drive) doesn't find any errors. Running SFC /SCANNOW to run system file checker Checked the list of profiles at HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows NT\CurrentVersion\ProfileList and ensured that each profile directory exists. I'm stumped; WHAT file can't be found and why is my backup failing? This is on a Lenovo T420 laptop.

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  • Windows 7 BSOD - ntoskrnl?

    - by Ken Mason
    2 new HP Pavilion notebooks with 7 Home Premium pre-loaded with Norton. My first act was to use the Norton Removal Tool and load ZoneAlarm free and AVG Free. Frequent random BSOD's ever since...I found my way into Debug and have had various reports regarding ntoskrnl, depending on the status of symbols. It's been many years since I played with (DOS 3.x) debug, so this has been a considerable fumble. Excerpts follow and any insights would be greatly appreciated, as I am not a developer: ADDITIONAL_DEBUG_TEXT: Use '!findthebuild' command to search for the target build information. If the build information is available, run '!findthebuild -s ; .reload' to set symbol path and load symbols. MODULE_NAME: nt FAULTING_MODULE: fffff8000305d000 nt DEBUG_FLR_IMAGE_TIMESTAMP: 4b88cfeb BUGCHECK_STR: 0x7f_8 CUSTOMER_CRASH_COUNT: 1 DEFAULT_BUCKET_ID: VISTA_DRIVER_FAULT CURRENT_IRQL: 0 LAST_CONTROL_TRANSFER: from fffff800030ccb69 to fffff800030cd600 STACK_TEXT: fffff80004d6fd28 fffff800030ccb69 : 000000000000007f 0000000000000008 0000000080050033 00000000000006f8 : nt+0x70600 fffff80004d6fd30 000000000000007f : 0000000000000008 0000000080050033 00000000000006f8 fffff80003095e58 : nt+0x6fb69 fffff80004d6fd38 0000000000000008 : 0000000080050033 00000000000006f8 fffff80003095e58 0000000000000000 : 0x7f fffff80004d6fd40 0000000080050033 : 00000000000006f8 fffff80003095e58 0000000000000000 0000000000000000 : 0x8 fffff80004d6fd48 00000000000006f8 : fffff80003095e58 0000000000000000 0000000000000000 0000000000000000 : 0x80050033 fffff80004d6fd50 fffff80003095e58 : 0000000000000000 0000000000000000 0000000000000000 0000000000000000 : 0x6f8 fffff80004d6fd58 0000000000000000 : 0000000000000000 0000000000000000 0000000000000000 0000000000000000 : nt+0x38e58 STACK_COMMAND: kb FOLLOWUP_IP: nt+70600 fffff800`030cd600 48894c2408 mov qword ptr [rsp+8],rcx SYMBOL_STACK_INDEX: 0 SYMBOL_NAME: nt+70600 FOLLOWUP_NAME: MachineOwner IMAGE_NAME: ntoskrnl.exe BUCKET_ID: WRONG_SYMBOLS Followup: MachineOwner ...................................................................... 0: kd !lmi nt Loaded Module Info: [nt] Module: ntkrnlmp Base Address: fffff8000305d000 Image Name: ntkrnlmp.exe Machine Type: 34404 (X64) Time Stamp: 4b88cfeb Sat Feb 27 00:55:23 2010 Size: 5dc000 CheckSum: 545094 Characteristics: 22 perf Debug Data Dirs: Type Size VA Pointer CODEVIEW 25, 19c65c, 19bc5c RSDS - GUID: {7E9A3CAB-6268-45DE-8E10-816E3080A3B7} Age: 2, Pdb: ntkrnlmp.pdb CLSID 4, 19c658, 19bc58 [Data not mapped] Image Type: FILE - Image read successfully from debugger. ntkrnlmp.exe Symbol Type: PDB - Symbols loaded successfully from symbol server. d:\debugsymbols\ntkrnlmp.pdb\7E9A3CAB626845DE8E10816E3080A3B72\ntkrnlmp.pdb Load Report: public symbols , not source indexed d:\debugsymbols\ntkrnlmp.pdb\7E9A3CAB626845DE8E10816E3080A3B72\ntkrnlmp.pdb 0: kd !analyze -v * Bugcheck Analysis * * UNEXPECTED_KERNEL_MODE_TRAP (7f) This means a trap occurred in kernel mode, and it's a trap of a kind that the kernel isn't allowed to have/catch (bound trap) or that is always instant death (double fault). The first number in the bugcheck params is the number of the trap (8 = double fault, etc) Consult an Intel x86 family manual to learn more about what these traps are. Here is a portion of those codes: If kv shows a taskGate use .tss on the part before the colon, then kv. Else if kv shows a trapframe use .trap on that value Else .trap on the appropriate frame will show where the trap was taken (on x86, this will be the ebp that goes with the procedure KiTrap) Endif kb will then show the corrected stack. Arguments: Arg1: 0000000000000008, EXCEPTION_DOUBLE_FAULT Arg2: 0000000080050033 Arg3: 00000000000006f8 Arg4: fffff80003095e58 Debugging Details: BUGCHECK_STR: 0x7f_8 CUSTOMER_CRASH_COUNT: 1 DEFAULT_BUCKET_ID: VISTA_DRIVER_FAULT PROCESS_NAME: System CURRENT_IRQL: 2 LAST_CONTROL_TRANSFER: from fffff800030ccb69 to fffff800030cd600 STACK_TEXT: fffff80004d6fd28 fffff800030ccb69 : 000000000000007f 0000000000000008 0000000080050033 00000000000006f8 : nt!KeBugCheckEx fffff80004d6fd30 fffff800030cb032 : 0000000000000000 0000000000000000 0000000000000000 0000000000000000 : nt!KiBugCheckDispatch+0x69 fffff80004d6fe70 fffff80003095e58 : 0000000000000000 0000000000000000 0000000000000000 0000000000000000 : nt!KiDoubleFaultAbort+0xb2 fffff880089efc60 0000000000000000 : 0000000000000000 0000000000000000 0000000000000000 0000000000000000 : nt!SeAccessCheckFromState+0x58 STACK_COMMAND: kb FOLLOWUP_IP: nt!KiDoubleFaultAbort+b2 fffff800`030cb032 90 nop SYMBOL_STACK_INDEX: 2 SYMBOL_NAME: nt!KiDoubleFaultAbort+b2 FOLLOWUP_NAME: MachineOwner MODULE_NAME: nt IMAGE_NAME: ntkrnlmp.exe DEBUG_FLR_IMAGE_TIMESTAMP: 4b88cfeb FAILURE_BUCKET_ID: X64_0x7f_8_nt!KiDoubleFaultAbort+b2 BUCKET_ID: X64_0x7f_8_nt!KiDoubleFaultAbort+b2 Followup: MachineOwner I tried running Rootkit Revealer but I don't think it works on x64 systems. Similarly Blacklight seems to have aged off. I'm running Sophos Anti-Rootkit now. So far so good...

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  • Windows 7 / Ubuntu Dualboot GRUB Problem.

    - by Tek
    I'd like to first say ahead of time that I'm running a RAID-0 Setup. 1.First of all, I'm glad Ubuntu 9.10 installed flawlessly and detected my RAID-0 setup just fine. The issue I'm having now is that I already had Windows 7 installed and made a small 12GB partition for Linux/Swap. I grabbed EasyBCD 2.0 to edit the W7 bootloader and configured it to use dual boot Grub2 because before it didn't even show the option for Ubuntu. The bootloader points to a file made in the windows directory made by EasyBCD called "C:\NST\AutoNeoGrub0.mbr" which is what I'm guessing grub is booting from. After that I got the option for booting Ubuntu. The problem is that it's sending me to the Grub prompt (probably because it's pointing to \NST|AutoNeoGrub0.mbr?), at first I didn't know what to do but I researched and have to type grub commands to manually boot into Ubuntu Linux. Ex: grubroot (hd0,4) grubkernel /boot/vmlinuz-2.6... root=/dev/disk/by-uuid/24624-2424... grubinitrd boot/initrd.img-2.6... grubboot After all that Ubuntu boots just fine, but how do I fix it permanently? Do I need to edit the bootloader manually (since Easy BCD "autoconfigures")? Some insight on this would rock! Also, it sucks to type the actual uuid since it's REALLY long. I tried getting the name of the drive via fdisk -l but since it's raid 0 I'm guessing I can't do that. How can I get a shorter name of the drive? like /dev/sda, /dev/sdb etc? I've also tried to update to the latest GRUB and I got this: Creating config file /etc/default/grub with new version Generating core.img error: cannot seek /dev/sdc' error: cannot seek/dev/sdc' grub-probe: error: no mapping exists for nvidia_dbedfcca5' Auto-detection of a filesystem module failed. Please specify the module with the option--modules' explicitly. dpkg: error processing grub-pc (--configure): subprocess installed post-installation script returned error exit status 1 dpkg: dependency problems prevent configuration of grub2: grub2 depends on grub-pc; however: Package grub-pc is not configured yet. dpkg: error processing grub2 (--configure): dependency problems - leaving unconfigured No apport report written because the error message indicates its a followup error from a previous failure. E: Sub-process /usr/bin/dpkg returned an error code (1) I've also tried: b@dnb:~$ sudo update-grub error: cannot seek /dev/sdc' error: cannot seek/dev/sdc' Generating grub.cfg ... Found linux image: /boot/vmlinuz-2.6.31-14-generic Found initrd image: /boot/initrd.img-2.6.31-14-generic error: cannot seek /dev/sdc' grub-probe: error: no mapping exists fornvidia_dbedfcca5' error: cannot seek /dev/sdc' grub-probe: error: no mapping exists fornvidia_dbedfcca5' Found memtest86+ image: /boot/memtest86+.bin Found Windows 7 (loader) on /dev/mapper/nvidia_dbedfcca1 error: cannot seek /dev/sdc' grub-probe: error: no mapping exists fornvidia_dbedfcca1' done To no avail. Any idea what I can do to fix this mess? :( Edit: This is my disk configuration. b@dnb:~$ sudo df -l Filesystem 1K-blocks Used Available Use% Mounted on /dev/mapper/nvidia_dbedfcca5 12302232 2744788 8932520 24% / udev 1030288 268 1030020 1% /dev none 1030288 964 1029324 1% /dev/shm none 1030288 92 1030196 1% /var/run none 1030288 0 1030288 0% /var/lock none 1030288 0 1030288 0% /lib/init/rw /dev/sr0 706532 706532 0 100% /media/cdrom0 Note: /dev/mapper/nvidia_dbedfcca5 is my Linux boot partition

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  • .htaccess template, suggestions needed.

    - by purpler
    I compiled myself a .htaccess template and would like to know whether the caching and compressions is set up right, constructive suggestions and critics needed. # Defaults AddDefaultCharset UTF-8 DefaultLanguage en-US FileETag None Header unset ETag ServerSignature Off SetEnv TZ Europe/Belgrade # Rewrites Options +FollowSymLinks RewriteEngine On RewriteBase / # Redirect to WWW RewriteCond %{HTTP_HOST} ^serpentineseo.com RewriteRule (.*) http://www.serpentineseo.com/$1 [R=301,L] # Redirect index to root RewriteCond %{THE_REQUEST} ^[A-Z]{3,9}\ /.*index\.html\ HTTP/ RewriteRule ^(.*)index\.html$ /$1 [R=301,L] # Cache media files: ExpiresActive On ExpiresDefault A0 # Month <filesMatch "\.(gif|jpg|jpeg|png|ico|swf|js)$"> Header set Cache-Control "max-age=2592000, public" </filesMatch> # Week <FilesMatch "\.(css|pdf)$"> Header set Cache-Control "max-age=604800" </FilesMatch> # 10 Min <FilesMatch "\.(html|htm|txt)$"> Header set Cache-Control "max-age=600" </FilesMatch> # Do not cache <FilesMatch "\.(pl|php|cgi|spl|scgi|fcgi)$"> Header unset Cache-Control </FilesMatch> # Compress output <IfModule mod_deflate.c> <FilesMatch "\.(html|js|css)$"> SetOutputFilter DEFLATE </FilesMatch> </IfModule> # Error Documents ErrorDocument 206 /error/206.html ErrorDocument 401 /error/401.html ErrorDocument 403 /error/403.html ErrorDocument 404 /error/404.html ErrorDocument 500 /error/500.html # Prevent hotlinking RewriteCond %{HTTP_REFERER} !^$ RewriteCond %{HTTP_REFERER} !^http://(www\.)?serpentineseo.com/.*$ [NC] RewriteRule \.(gif|jpg|png)$ http://www.serpentineseo.com/images/angryman.png [R,L] # Prevent offline browsers RewriteCond %{HTTP_USER_AGENT} ^BlackWidow [OR] RewriteCond %{HTTP_USER_AGENT} ^Bot\ mailto:[email protected] [OR] RewriteCond %{HTTP_USER_AGENT} ^ChinaClaw [OR] RewriteCond %{HTTP_USER_AGENT} ^Custo [OR] RewriteCond %{HTTP_USER_AGENT} ^DISCo [OR] RewriteCond %{HTTP_USER_AGENT} ^Download\ Demon [OR] RewriteCond %{HTTP_USER_AGENT} ^eCatch [OR] RewriteCond %{HTTP_USER_AGENT} ^EirGrabber [OR] RewriteCond %{HTTP_USER_AGENT} ^EmailSiphon [OR] RewriteCond %{HTTP_USER_AGENT} ^EmailWolf [OR] RewriteCond %{HTTP_USER_AGENT} ^Express\ WebPictures [OR] RewriteCond %{HTTP_USER_AGENT} ^ExtractorPro [OR] RewriteCond %{HTTP_USER_AGENT} ^EyeNetIE [OR] RewriteCond %{HTTP_USER_AGENT} ^FlashGet [OR] RewriteCond %{HTTP_USER_AGENT} ^GetRight [OR] RewriteCond %{HTTP_USER_AGENT} ^GetWeb! [OR] RewriteCond %{HTTP_USER_AGENT} ^Go!Zilla [OR] RewriteCond %{HTTP_USER_AGENT} ^Go-Ahead-Got-It [OR] RewriteCond %{HTTP_USER_AGENT} ^GrabNet [OR] RewriteCond %{HTTP_USER_AGENT} ^Grafula [OR] RewriteCond %{HTTP_USER_AGENT} ^HMView [OR] RewriteCond %{HTTP_USER_AGENT} HTTrack [NC,OR] RewriteCond %{HTTP_USER_AGENT} ^Image\ Stripper [OR] RewriteCond %{HTTP_USER_AGENT} ^Image\ Sucker [OR] RewriteCond %{HTTP_USER_AGENT} Indy\ Library [NC,OR] RewriteCond %{HTTP_USER_AGENT} ^InterGET [OR] RewriteCond %{HTTP_USER_AGENT} ^Internet\ Ninja [OR] RewriteCond %{HTTP_USER_AGENT} ^JetCar [OR] RewriteCond %{HTTP_USER_AGENT} ^JOC\ Web\ Spider [OR] RewriteCond %{HTTP_USER_AGENT} ^larbin [OR] RewriteCond %{HTTP_USER_AGENT} ^LeechFTP [OR] RewriteCond %{HTTP_USER_AGENT} ^Mass\ Downloader [OR] RewriteCond %{HTTP_USER_AGENT} ^MIDown\ tool [OR] RewriteCond %{HTTP_USER_AGENT} ^Mister\ PiX [OR] RewriteCond %{HTTP_USER_AGENT} ^Navroad [OR] RewriteCond %{HTTP_USER_AGENT} ^NearSite [OR] RewriteCond %{HTTP_USER_AGENT} ^NetAnts [OR] RewriteCond %{HTTP_USER_AGENT} ^NetSpider [OR] RewriteCond %{HTTP_USER_AGENT} ^Net\ Vampire [OR] RewriteCond %{HTTP_USER_AGENT} ^NetZIP [OR] RewriteCond %{HTTP_USER_AGENT} ^Octopus [OR] RewriteCond %{HTTP_USER_AGENT} ^Offline\ Explorer [OR] RewriteCond %{HTTP_USER_AGENT} ^Offline\ Navigator [OR] RewriteCond %{HTTP_USER_AGENT} ^PageGrabber [OR] RewriteCond %{HTTP_USER_AGENT} ^Papa\ Foto [OR] RewriteCond %{HTTP_USER_AGENT} ^pavuk [OR] RewriteCond %{HTTP_USER_AGENT} ^pcBrowser [OR] RewriteCond %{HTTP_USER_AGENT} ^RealDownload [OR] RewriteCond %{HTTP_USER_AGENT} ^ReGet [OR] RewriteCond %{HTTP_USER_AGENT} ^SiteSnagger [OR] RewriteCond %{HTTP_USER_AGENT} ^SmartDownload [OR] RewriteCond %{HTTP_USER_AGENT} ^SuperBot [OR] RewriteCond %{HTTP_USER_AGENT} ^SuperHTTP [OR] RewriteCond %{HTTP_USER_AGENT} ^Surfbot [OR] RewriteCond %{HTTP_USER_AGENT} ^tAkeOut [OR] RewriteCond %{HTTP_USER_AGENT} ^Teleport\ Pro [OR] RewriteCond %{HTTP_USER_AGENT} ^VoidEYE [OR] RewriteCond %{HTTP_USER_AGENT} ^Web\ Image\ Collector [OR] RewriteCond %{HTTP_USER_AGENT} ^Web\ Sucker [OR] RewriteCond %{HTTP_USER_AGENT} ^WebAuto [OR] RewriteCond %{HTTP_USER_AGENT} ^WebCopier [OR] RewriteCond %{HTTP_USER_AGENT} ^WebFetch [OR] RewriteCond %{HTTP_USER_AGENT} ^WebGo\ IS [OR] RewriteCond %{HTTP_USER_AGENT} ^WebLeacher [OR] RewriteCond %{HTTP_USER_AGENT} ^WebReaper [OR] RewriteCond %{HTTP_USER_AGENT} ^WebSauger [OR] RewriteCond %{HTTP_USER_AGENT} ^Website\ eXtractor [OR] RewriteCond %{HTTP_USER_AGENT} ^Website\ Quester [OR] RewriteCond %{HTTP_USER_AGENT} ^WebStripper [OR] RewriteCond %{HTTP_USER_AGENT} ^WebWhacker [OR] RewriteCond %{HTTP_USER_AGENT} ^WebZIP [OR] RewriteCond %{HTTP_USER_AGENT} ^Wget [OR] RewriteCond %{HTTP_USER_AGENT} ^Widow [OR] RewriteCond %{HTTP_USER_AGENT} ^WWWOFFLE [OR] RewriteCond %{HTTP_USER_AGENT} ^Xaldon\ WebSpider [OR] RewriteCond %{HTTP_USER_AGENT} ^Zeus RewriteRule ^.*$ http://www.google.com [R,L] # Protect against DOS attacks by limiting file upload size LimitRequestBody 10240000 # Deny access to sensitive files <FilesMatch "\.(htaccess|psd|log)$"> Order Allow,Deny Deny from all </FilesMatch>

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  • Integrating HTML into Silverlight Applications

    - by dwahlin
    Looking for a way to display HTML content within a Silverlight application? If you haven’t tried doing that before it can be challenging at first until you know a few tricks of the trade.  Being able to display HTML is especially handy when you’re required to display RSS feeds (with embedded HTML), SQL Server Reporting Services reports, PDF files (not actually HTML – but the techniques discussed will work), or other HTML content.  In this post I'll discuss three options for displaying HTML content in Silverlight applications and describe how my company is using these techniques in client applications. Displaying HTML Overlays If you need to display HTML over a Silverlight application (such as an RSS feed containing HTML data in it) you’ll need to set the Silverlight control’s windowless parameter to true. This can be done using the object tag as shown next: <object data="data:application/x-silverlight-2," type="application/x-silverlight-2" width="100%" height="100%"> <param name="source" value="ClientBin/HTMLAndSilverlight.xap"/> <param name="onError" value="onSilverlightError" /> <param name="background" value="white" /> <param name="minRuntimeVersion" value="4.0.50401.0" /> <param name="autoUpgrade" value="true" /> <param name="windowless" value="true" /> <a href="http://go.microsoft.com/fwlink/?LinkID=149156&v=4.0.50401.0" style="text-decoration:none"> <img src="http://go.microsoft.com/fwlink/?LinkId=161376" alt="Get Microsoft Silverlight" style="border-style:none"/> </a> </object> By setting the control to “windowless” you can overlay HTML objects by using absolute positioning and other CSS techniques. Keep in mind that on Windows machines the windowless setting can result in a performance hit when complex animations or HD video are running since the plug-in content is displayed directly by the browser window. It goes without saying that you should only set windowless to true when you really need the functionality it offers. For example, if I want to display my blog’s RSS content on top of a Silverlight application I could set windowless to true and create a user control that grabbed the content and output it using a DataList control: <style type="text/css"> a {text-decoration:none;font-weight:bold;font-size:14pt;} </style> <div style="margin-top:10px; margin-left:10px;margin-right:5px;"> <asp:DataList ID="RSSDataList" runat="server" DataSourceID="RSSDataSource"> <ItemTemplate> <a href='<%# XPath("link") %>'><%# XPath("title") %></a> <br /> <%# XPath("description") %> <br /> </ItemTemplate> </asp:DataList> <asp:XmlDataSource ID="RSSDataSource" DataFile="http://weblogs.asp.net/dwahlin/rss.aspx" XPath="rss/channel/item" CacheDuration="60" runat="server" /> </div> The user control can then be placed in the page hosting the Silverlight control as shown below. This example adds a Close button, additional content to display in the overlay window and the HTML generated from the user control. <div id="RSSDiv"> <div style="background-color:#484848;border:1px solid black;height:35px;width:100%;"> <img alt="Close Button" align="right" src="Images/Close.png" onclick="HideOverlay();" style="cursor:pointer;" /> </div> <div style="overflow:auto;width:800px;height:565px;"> <div style="float:left;width:100px;height:103px;margin-left:10px;margin-top:5px;"> <img src="http://weblogs.asp.net/blogs/dwahlin/dan2008.jpg" style="border:1px solid Gray" /> </div> <div style="float:left;width:300px;height:103px;margin-top:5px;"> <a href="http://weblogs.asp.net/dwahlin" style="margin-left:10px;font-size:20pt;">Dan Wahlin's Blog</a> </div> <br /><br /><br /> <div style="clear:both;margin-top:20px;"> <uc:BlogRoller ID="BlogRoller" runat="server" /> </div> </div> </div> Of course, we wouldn’t want the RSS HTML content to be shown until requested. Once it’s requested the absolute position of where it should show above the Silverlight control can be set using standard CSS styles. The following ID selector named #RSSDiv handles hiding the overlay div shown above and determines where it will be display on the screen. #RSSDiv { background-color:White; position:absolute; top:100px; left:300px; width:800px; height:600px; border:1px solid black; display:none; } Now that the HTML content to display above the Silverlight control is set, how can we show it as a user clicks a HyperlinkButton or other control in the application? Fortunately, Silverlight provides an excellent HTML bridge that allows direct access to content hosted within a page. The following code shows two JavaScript functions that can be called from Siverlight to handle showing or hiding HTML overlay content. The two functions rely on jQuery (http://www.jQuery.com) to make it easy to select HTML objects and manipulate their properties: function ShowOverlay() { rssDiv.css('display', 'block'); } function HideOverlay() { rssDiv.css('display', 'none'); } Calling the ShowOverlay function is as simple as adding the following code into the Silverlight application within a button’s Click event handler: private void OverlayHyperlinkButton_Click(object sender, RoutedEventArgs e) { HtmlPage.Window.Invoke("ShowOverlay"); } The result of setting the Silverlight control’s windowless parameter to true and showing the HTML overlay content is shown in the following screenshot:   Thinking Outside the Box to Show HTML Content Setting the windowless parameter to true may not be a viable option for some Silverlight applications or you may simply want to go about showing HTML content a different way. The next technique I’ll show takes advantage of simple HTML, CSS and JavaScript code to handle showing HTML content while a Silverlight application is running in the browser. Keep in mind that with Silverlight’s HTML bridge feature you can always pop-up HTML content in a new browser window using code similar to the following: System.Windows.Browser.HtmlPage.Window.Navigate( new Uri("http://silverlight.net"), "_blank"); For this example I’ll demonstrate how to hide the Silverlight application while maximizing a container div containing the HTML content to show. This allows HTML content to take up the full screen area of the browser without having to set windowless to true and when done right can make the user feel like they never left the Silverlight application. The following HTML shows several div elements that are used to display HTML within the same browser window as the Silverlight application: <div id="JobPlanDiv"> <div style="vertical-align:middle"> <img alt="Close Button" align="right" src="Images/Close.png" onclick="HideJobPlanIFrame();" style="cursor:pointer;" /> </div> <div id="JobPlan_IFrame_Container" style="height:95%;width:100%;margin-top:37px;"></div> </div> The JobPlanDiv element acts as a container for two other divs that handle showing a close button and hosting an iframe that will be added dynamically at runtime. JobPlanDiv isn’t visible when the Silverlight application loads due to the following ID selector added into the page: #JobPlanDiv { position:absolute; background-color:#484848; overflow:hidden; left:0; top:0; height:100%; width:100%; display:none; } When the HTML content needs to be shown or hidden the JavaScript functions shown next can be used: var jobPlanIFrameID = 'JobPlan_IFrame'; var slHost = null; var jobPlanContainer = null; var jobPlanIFrameContainer = null; var rssDiv = null; $(document).ready(function () { slHost = $('#silverlightControlHost'); jobPlanContainer = $('#JobPlanDiv'); jobPlanIFrameContainer = $('#JobPlan_IFrame_Container'); rssDiv = $('#RSSDiv'); }); function ShowJobPlanIFrame(url) { jobPlanContainer.css('display', 'block'); $('<iframe id="' + jobPlanIFrameID + '" src="' + url + '" style="height:100%;width:100%;" />') .appendTo(jobPlanIFrameContainer); slHost.css('width', '0%'); } function HideJobPlanIFrame() { jobPlanContainer.css('display', 'none'); $('#' + jobPlanIFrameID).remove(); slHost.css('width', '100%'); } ShowJobPlanIFrame() handles showing the JobPlanDiv div and adding an iframe into it dynamically. Once JobPlanDiv is shown, the Silverlight control host has its width set to a value of 0% to allow the control to stay alive while making it invisible to the user. I found that this technique works better across multiple browsers as opposed to manipulating the Silverlight control host div’s display or visibility properties. Now that you’ve seen the code to handle showing and hiding the HTML content area, let’s switch focus to the Silverlight application. As a user clicks on a link such as “View Report” the ShowJobPlanIFrame() JavaScript function needs to be called. The following code handles that task: private void ReportHyperlinkButton_Click(object sender, RoutedEventArgs e) { ShowBrowser(_BaseUrl + "/Report.aspx"); } public void ShowBrowser(string url) { HtmlPage.Window.Invoke("ShowJobPlanIFrame", url); } Any URL can be passed into the ShowBrowser() method which handles invoking the JavaScript function. This includes standard web pages or even PDF files. We’ve used this technique frequently with our SmartPrint control (http://www.smartwebcontrols.com) which converts Silverlight screens into PDF documents and displays them. Here’s an example of the content generated:   Silverlight 4’s WebBrowser Control Both techniques shown to this point work well when Silverlight is running in-browser but not so well when it’s running out-of-browser since there’s no host page that you can access using the HTML bridge. Fortunately, Silverlight 4 provides a WebBrowser control that can be used to perform the same functionality quite easily. We’re currently using it in client applications to display PDF documents, SSRS reports and standard HTML content. Using the WebBrowser control simplifies the application quite a bit since no JavaScript is required if the application only runs out-of-browser. Here’s a simple example of defining the WebBrowser control in XAML. I typically define it in MainPage.xaml when a Silverlight Navigation template is used to create the project so that I can re-use the functionality across multiple screens. <Grid x:Name="WebBrowserGrid" HorizontalAlignment="Stretch" VerticalAlignment="Stretch" Visibility="Collapsed"> <StackPanel HorizontalAlignment="Stretch" VerticalAlignment="Stretch"> <Border Background="#484848" HorizontalAlignment="Stretch" Height="40"> <Image x:Name="WebBrowserImage" Width="100" Height="33" Cursor="Hand" HorizontalAlignment="Right" Source="/HTMLAndSilverlight;component/Assets/Images/Close.png" MouseLeftButtonDown="WebBrowserImage_MouseLeftButtonDown" /> </Border> <WebBrowser x:Name="JobPlanReportWebBrowser" HorizontalAlignment="Stretch" VerticalAlignment="Stretch" /> </StackPanel> </Grid> Looking through the XAML you can see that a close image is defined along with the WebBrowser control. Because the URL that the WebBrowser should navigate to isn’t known at design time no value is assigned to the control’s Source property. If the XAML shown above is left “as is” you’ll find that any HTML content assigned to the WebBrowser doesn’t display properly. This is due to no height or width being set on the control. To handle this issue the following code is added into the XAML’s code-behind file to dynamically determine the height and width of the page and assign it to the WebBrowser. This is done by handling the SizeChanged event. void MainPage_SizeChanged(object sender, SizeChangedEventArgs e) { WebBrowserGrid.Height = JobPlanReportWebBrowser.Height = ActualHeight; WebBrowserGrid.Width = JobPlanReportWebBrowser.Width = ActualWidth; } When the user wants to view HTML content they click a button which executes the code shown in next: public void ShowBrowser(string url) { if (Application.Current.IsRunningOutOfBrowser) { JobPlanReportWebBrowser.NavigateToString("<html><body><iframe src='" + url + "' style='width:100%;height:97%;' /></body></html>"); WebBrowserGrid.Visibility = Visibility.Visible; } else { HtmlPage.Window.Invoke("ShowJobPlanIFrame", url); } } private void WebBrowserImage_MouseLeftButtonDown(object sender, MouseButtonEventArgs e) { WebBrowserGrid.Visibility = Visibility.Collapsed; }   Looking through the code you’ll see that it checks to see if the Silverlight application is running out-of-browser and then either displays the WebBrowser control or runs the JavaScript function discussed earlier. Although the WebBrowser control’s Source property could be assigned the URI of the page to navigate to, by assigning HTML content using the NavigateToString() method and adding an iframe, content can be shown from any site including cross-domain sites. This is especially handy when you need to grab a page from a reporting site that’s in a different domain than the Silverlight application. Here’s an example of viewing  PDF file inside of an out-of-browser application. The first image shows the application running out-of-browser before the user clicks a PDF HyperlinkButton.  The second image shows the PDF being displayed.   While there are certainly other techniques that can be used, the ones shown here have worked well for us in different applications and provide the ability to display HTML content in-browser or out-of-browser. Feel free to add a comment if you have another tip or trick you like to use when working with HTML content in Silverlight applications.   Download Code Sample   For more information about onsite, online and video training, mentoring and consulting solutions for .NET, SharePoint or Silverlight please visit http://www.thewahlingroup.com.

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  • From Binary to Data Structures

    - by Cédric Menzi
    Table of Contents Introduction PE file format and COFF header COFF file header BaseCoffReader Byte4ByteCoffReader UnsafeCoffReader ManagedCoffReader Conclusion History This article is also available on CodeProject Introduction Sometimes, you want to parse well-formed binary data and bring it into your objects to do some dirty stuff with it. In the Windows world most data structures are stored in special binary format. Either we call a WinApi function or we want to read from special files like images, spool files, executables or may be the previously announced Outlook Personal Folders File. Most specifications for these files can be found on the MSDN Libarary: Open Specification In my example, we are going to get the COFF (Common Object File Format) file header from a PE (Portable Executable). The exact specification can be found here: PECOFF PE file format and COFF header Before we start we need to know how this file is formatted. The following figure shows an overview of the Microsoft PE executable format. Source: Microsoft Our goal is to get the PE header. As we can see, the image starts with a MS-DOS 2.0 header with is not important for us. From the documentation we can read "...After the MS DOS stub, at the file offset specified at offset 0x3c, is a 4-byte...". With this information we know our reader has to jump to location 0x3c and read the offset to the signature. The signature is always 4 bytes that ensures that the image is a PE file. The signature is: PE\0\0. To prove this we first seek to the offset 0x3c, read if the file consist the signature. So we need to declare some constants, because we do not want magic numbers.   private const int PeSignatureOffsetLocation = 0x3c; private const int PeSignatureSize = 4; private const string PeSignatureContent = "PE";   Then a method for moving the reader to the correct location to read the offset of signature. With this method we always move the underlining Stream of the BinaryReader to the start location of the PE signature.   private void SeekToPeSignature(BinaryReader br) { // seek to the offset for the PE signagure br.BaseStream.Seek(PeSignatureOffsetLocation, SeekOrigin.Begin); // read the offset int offsetToPeSig = br.ReadInt32(); // seek to the start of the PE signature br.BaseStream.Seek(offsetToPeSig, SeekOrigin.Begin); }   Now, we can check if it is a valid PE image by reading of the next 4 byte contains the content PE.   private bool IsValidPeSignature(BinaryReader br) { // read 4 bytes to get the PE signature byte[] peSigBytes = br.ReadBytes(PeSignatureSize); // convert it to a string and trim \0 at the end of the content string peContent = Encoding.Default.GetString(peSigBytes).TrimEnd('\0'); // check if PE is in the content return peContent.Equals(PeSignatureContent); }   With this basic functionality we have a good base reader class to try the different methods of parsing the COFF file header. COFF file header The COFF header has the following structure: Offset Size Field 0 2 Machine 2 2 NumberOfSections 4 4 TimeDateStamp 8 4 PointerToSymbolTable 12 4 NumberOfSymbols 16 2 SizeOfOptionalHeader 18 2 Characteristics If we translate this table to code, we get something like this:   [StructLayout(LayoutKind.Sequential, CharSet = CharSet.Unicode)] public struct CoffHeader { public MachineType Machine; public ushort NumberOfSections; public uint TimeDateStamp; public uint PointerToSymbolTable; public uint NumberOfSymbols; public ushort SizeOfOptionalHeader; public Characteristic Characteristics; } BaseCoffReader All readers do the same thing, so we go to the patterns library in our head and see that Strategy pattern or Template method pattern is sticked out in the bookshelf. I have decided to take the template method pattern in this case, because the Parse() should handle the IO for all implementations and the concrete parsing should done in its derived classes.   public CoffHeader Parse() { using (var br = new BinaryReader(File.Open(_fileName, FileMode.Open, FileAccess.Read, FileShare.Read))) { SeekToPeSignature(br); if (!IsValidPeSignature(br)) { throw new BadImageFormatException(); } return ParseInternal(br); } } protected abstract CoffHeader ParseInternal(BinaryReader br);   First we open the BinaryReader, seek to the PE signature then we check if it contains a valid PE signature and rest is done by the derived implementations. Byte4ByteCoffReader The first solution is using the BinaryReader. It is the general way to get the data. We only need to know which order, which data-type and its size. If we read byte for byte we could comment out the first line in the CoffHeader structure, because we have control about the order of the member assignment.   protected override CoffHeader ParseInternal(BinaryReader br) { CoffHeader coff = new CoffHeader(); coff.Machine = (MachineType)br.ReadInt16(); coff.NumberOfSections = (ushort)br.ReadInt16(); coff.TimeDateStamp = br.ReadUInt32(); coff.PointerToSymbolTable = br.ReadUInt32(); coff.NumberOfSymbols = br.ReadUInt32(); coff.SizeOfOptionalHeader = (ushort)br.ReadInt16(); coff.Characteristics = (Characteristic)br.ReadInt16(); return coff; }   If the structure is as short as the COFF header here and the specification will never changed, there is probably no reason to change the strategy. But if a data-type will be changed, a new member will be added or ordering of member will be changed the maintenance costs of this method are very high. UnsafeCoffReader Another way to bring the data into this structure is using a "magically" unsafe trick. As above, we know the layout and order of the data structure. Now, we need the StructLayout attribute, because we have to ensure that the .NET Runtime allocates the structure in the same order as it is specified in the source code. We also need to enable "Allow unsafe code (/unsafe)" in the project's build properties. Then we need to add the following constructor to the CoffHeader structure.   [StructLayout(LayoutKind.Sequential, CharSet = CharSet.Unicode)] public struct CoffHeader { public CoffHeader(byte[] data) { unsafe { fixed (byte* packet = &data[0]) { this = *(CoffHeader*)packet; } } } }   The "magic" trick is in the statement: this = *(CoffHeader*)packet;. What happens here? We have a fixed size of data somewhere in the memory and because a struct in C# is a value-type, the assignment operator = copies the whole data of the structure and not only the reference. To fill the structure with data, we need to pass the data as bytes into the CoffHeader structure. This can be achieved by reading the exact size of the structure from the PE file.   protected override CoffHeader ParseInternal(BinaryReader br) { return new CoffHeader(br.ReadBytes(Marshal.SizeOf(typeof(CoffHeader)))); }   This solution is the fastest way to parse the data and bring it into the structure, but it is unsafe and it could introduce some security and stability risks. ManagedCoffReader In this solution we are using the same approach of the structure assignment as above. But we need to replace the unsafe part in the constructor with the following managed part:   [StructLayout(LayoutKind.Sequential, CharSet = CharSet.Unicode)] public struct CoffHeader { public CoffHeader(byte[] data) { IntPtr coffPtr = IntPtr.Zero; try { int size = Marshal.SizeOf(typeof(CoffHeader)); coffPtr = Marshal.AllocHGlobal(size); Marshal.Copy(data, 0, coffPtr, size); this = (CoffHeader)Marshal.PtrToStructure(coffPtr, typeof(CoffHeader)); } finally { Marshal.FreeHGlobal(coffPtr); } } }     Conclusion We saw that we can parse well-formed binary data to our data structures using different approaches. The first is probably the clearest way, because we know each member and its size and ordering and we have control about the reading the data for each member. But if add member or the structure is going change by some reason, we need to change the reader. The two other solutions use the approach of the structure assignment. In the unsafe implementation we need to compile the project with the /unsafe option. We increase the performance, but we get some security risks.

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