ios - Save image data to sqlite database in iphone -


i want save image data sqlite database can't ... 

- (void) savedata: (article*) article :(nsmutablearray*) rsslist {     sqlite3_stmt *statement;      if (sqlite3_open([self.databasepath utf8string], &articlesdb) == sqlite_ok)     {         nsstring* sqlformat = @"insert articles (guid, title, summary, mainlink, pubdate, author, imagelink, body, favorites, smallimage) values ('%@', '%@', '%@', '%@', '%@', '%@', '%@', '%@', '%@', ?)";         // correct summary.         nsstring* summary = [nsstring stringwithstring:article.summary];         summary           = [summary stringbyreplacingoccurrencesofstring:@"'" withstring:@"''"];         // correct title         nsstring* title   = [nsstring stringwithstring:article.title];         title             = [title stringbyreplacingoccurrencesofstring:@"'" withstring:@"''"];         // correct body         nsstring* body    = [nsstring stringwithstring:article.body];         //body              = [body stringbyreplacingoccurrencesofstring:@"'" withstring:@"''"];         // create insert sql query.         nsstring* insertsql = [nsstring stringwithformat:sqlformat, article.guid, title, summary, article.mainlink, article.pubdate, article.author, article.imagelink, body, article.favorite ? @"yes" : @"no"];         // add database.         sqlite3_prepare_v2(articlesdb, [insertsql utf8string], -1, &statement, null);         if (sqlite3_step(statement) == sqlite_done)         {             // add list.             [rsslist addobject:article];             // write log.             nslog( @"article added ... " );         }          else         {             nslog( @"failed add article. error is:  %s", sqlite3_errmsg(articlesdb) );         }          sqlite3_finalize(statement);         sqlite3_close(articlesdb);     } }

you can see have query , @ end have smallimage , value (?)

@"insert articles (guid, title, summary, mainlink, pubdate, author, imagelink, body, favorites, smallimage) values ('%@', '%@', '%@', '%@', '%@', '%@', '%@', '%@', '%@', ?)";

i have function must update image value somewhere in program: in function select row image link url when try write data last column "smallimage" no result ... when open database file editor see in last row "null" data not saved ...

- (void) savesmallimage: (nsdata*) imgdata :(nsstring*) mainurl {     if (sqlite3_open([self.databasepath utf8string], &articlesdb) == sqlite_ok)      {         nsstring* sqlitequery = [nsstring stringwithformat:@"select * articles imagelink =  '%@'", mainurl];          sqlite3_stmt* statement;          if( sqlite3_prepare_v2(articlesdb, [sqlitequery utf8string], -1, &statement, null) == sqlite_ok )          {             sqlite3_bind_blob(statement, 9, [imgdata bytes], [imgdata length], sqlite_transient);             sqlite3_step(statement);         }         else         {             nslog( @"savebody: failed sqlite3_prepare_v2. error is:  %s", sqlite3_errmsg(articlesdb) );         }          // finalize , close database.         sqlite3_finalize(statement);         sqlite3_close(articlesdb);     }     else      {         nslog(@"savesmallimage: failed sqlite3_open. error is: %s", sqlite3_errmsg(articlesdb) );     } }

who can tell me wrong ...

here how can save image sqlite:

// create images table. sql_stmp = "create table if not exists images (url text unique, image blob)"; if( sqlite3_exec(articlesdb, sql_stmp, null, null, &errmsg) != sqlite_ok )     nslog( @"fail create \"images\" table. error is: %@", errmsg );

and here function save:

// save small image data given main url  - (void) saveimagestosql: (nsdata*) imgdata :(nsstring*) mainurl {     nslog( @"\n*****save image sqlite*****\n" );      const char* sqlitequery = "insert images (url, image) values (?, ?)";     sqlite3_stmt* statement;      if( sqlite3_prepare_v2(articlesdb, sqlitequery, -1, &statement, null) == sqlite_ok )     {         sqlite3_bind_text(statement, 1, [mainurl utf8string], -1, sqlite_transient);         sqlite3_bind_blob(statement, 2, [imgdata bytes], [imgdata length], sqlite_transient);         sqlite3_step(statement);     }     else nslog( @"savebody: failed sqlite3_prepare_v2. error is:  %s", sqlite3_errmsg(articlesdb) );      // finalize , close database.     sqlite3_finalize(statement); }

and here function load images:

// load images data base given image url  - (nsdata*) loadimagesfromsql: (nsstring*) imagelink {     nsdata* data = nil;     nsstring* sqlitequery = [nsstring stringwithformat:@"select image images url = '%@'", imagelink];         sqlite3_stmt* statement;      if( sqlite3_prepare_v2(articlesdb, [sqlitequery utf8string], -1, &statement, null) == sqlite_ok )     {         if( sqlite3_step(statement) == sqlite_row )         {             int length = sqlite3_column_bytes(statement, 0);             data       = [nsdata datawithbytes:sqlite3_column_blob(statement, 0) length:length];         }     }      // finalize , close database.     sqlite3_finalize(statement);      return data;  }

Comments

Post a Comment

Popular posts from this blog

Is there a better way to structure post methods in Class Based Views -

i'm using class based views in django , never specify url in ajax calls , omit action parameter in form because know these requests go through post method of class based view. notice view - profile page make many requests depending on user updating on page - post method become convoluted , if/else mess example: def post(self, request, *args, **kwargs): # handle user changing available date if request.post.get('availabledate') != none: self.updateavailabledate(request) return jsonresponse({'result':'success'}) if request.post.get('newprojectname') != none: creative_user = creativeuserprofile.objects.get(id = request.user.id) project = project.create_project(creative_user, request.post['newprojectname']) project.save() return jsonresponse({'projectid': project.id }) if request.post.get('projectimage') != none , request.files['file']: proj
Read more

performance - Why is XCHG reg, reg a 3 micro-op instruction on modern Intel architectures? -

i'm doing micro-optimization on performance critical part of code , came across sequence of instructions (in at&t syntax): add %rax, %rbx mov %rdx, %rax mov %rbx, %rdx i thought had use case xchg allow me shave instruction , write: add %rbx, %rax xchg %rax, %rdx however, dimay found agner fog's instruction tables , xchg 3 micro-op instruction 2 cycle latency on sandy bridge, ivy bridge, broadwell, haswell , skylake. 3 whole micro-ops , 2 cycles of latency! 3 micro-ops throws off 4-1-1-1 cadence , 2 cycle latency makes worse original in best case since last 2 instructions in original might execute in parallel. now... cpu might breaking instruction micro-ops equivalent to: mov %rax, %tmp mov %rdx, %rax mov %tmp, %rdx where tmp anonymous internal register , suppose last 2 micro-ops run in parallel latency 2 cycles. given register renaming occurs on these micro-architectures, though, doesn't make sense me done way. why wouldn't register renamer
Read more

jquery - Responsive Navbar with Sub Navbar -

good day, forgive me nav vocabulary not best. if question confusing apologize. i'm working on navigation bar needs centered on page @ 768px , above. items in nav open (or perhaps toggle) subnav lives directly below. these nav should appear centered on page. i have been able work through responsive portion of nav bar, having main items align vertically , sub nav menu of each item roll out below, , gave them indent separation. working well. however, issue not responsive side, behavior @ width greater 768px. happens toggling menu's sub navigation pushes other main items down page below sub nav. here's code: $(document).ready(function () { //stick in fixed 100% height behind navbar don't wrap $('#slide-nav.navbar-inverse').after($('<div class="inverse" id="navbar-height-col"></div>')); $('#slide-nav.navbar-default').after($('<div id="navbar-height-col"></d
Read more