c# - System.Convert.ToBase64String returning different result than the input to System.Convert.FromBase64String -

i'm writing web application saves images web database. currently, use save images follows:

[webmethod] public static void save(string pictures) {     // pictures object containing url of image along metadata     list<imageobject> imagelist = new javascriptserializer().deserialize<list<imageobject>>(pictures);     (int = 0; < imagelist.count; i++)     {         var webclient = new webclient();         byte[] bytearray = webclient.downloaddata(imagelist[i].url);         imagelist[i].picture = bytearray;     }     // sql save imagelist } 

imageobject:

[datacontract] public class imageobject {     [datamember]     public string url { get; set; }     [datamember]     public string picture { get; set; } } 

now, works fine downloading url. entry saved database:

0xffd8ffe000104a464946000101[...]331b7cca7f0ad3a02dc8898f 

to display image, callsystem.convert.tobase64string()after retrieving , use imagesrc. however, trying add functionality users upload own pictures. function this, called an<input />:

function uploadpicture(){     var numpics = document.getelementbyid("uploadedpictures").files.length;     var ofreader = new filereader();     ofreader.onload = function (ofrevent) {         var src = ofrevent.target.result;         document.getelementbyid('image').src = src;     }     ofreader.readasdataurl(document.getelementbyid("uploadedpictures").files.length; } 

when using this, image source browser (over 2 mb when original ~500 kb):

data:image/bmp;base64,/9j/4aaqskzjrgabageay[...]k8ttmzebcsebseryem493ihafihwq6vklov/z 

this gets displayed when used source. however, since not actual url (andwebclient.downloaddata()is restricted urls of < 260 characters), have been trying other methods save data database. however, cannot seem find function save in same format aswebclient.downloaddata(). example, have looked @ converting base 64 string image , saving it, of answers seem useconvert.frombase64string(), using appears save in different format database:

0x64006100740061003a0069006d0[...]10051004500420041005100450042004 

trying usesystem.convert.tobase64string()on returns

zabhahqayqa6agkabqbhagcazqavagiabqbwadsaygbh[...]uwblafiawqblag0anaa5admasqbiaeeazgbpaegavwbxadyadgblagwatwb2ac8awga= 

which different usedconvert.frombase64string()on. other things found on google try , save in same format or display image have not worked far.

hence, wondering whether there exists method convert result afilereaderto same format aswebclient.downloaddata()does urls or if there way convert the0x6400[...]data format can displayed using an<img>source.

it turns out reason data saved database began with0x64006100[....]instead of0xffd8ffe0[...]was due me forgetting strip uri of initialdata:image;base64,. after doing this, saves , read usingsystem.convert.tobase64string().