在iOS下用sqlite數據庫存儲圖片，先把你的圖片轉換成 NSData 形式，然後在數據庫添加一行 blob 數據
假定數據庫中存在表 test_table(name,image), 下面代碼將圖片文件test.png的二進制數據寫到sqlite數據庫：
CHAR *name = "test";
NSString * nameString = [NSString stringWithCString:name encoding:NSUTF8StringEncoding];
NSString * filePath = [[NSBundle mainBundle] pathForResource:nameString ofType:@"png"];
IF ([[NSFileManager defaultManager] fileExistsAtPath:filePath])
{
NSData * imgData = UIImagePNGRepresentation([UIImage imageWithContentsOfFile:filePath]);
const CHAR * sequel = "insert into test_table(name,image) values(?,?)";
sqlite3_stmt * UPDATE;
IF (sqlite3_prepare_v2(DATABASE, sequel, -1, &UPDATE, NULL) == SQLITE_OK)
{
sqlite3_bind_text(UPDATE, 1, name, -1, NULL);
sqlite3_bind_blob(UPDATE, 2, [imgData bytes], [imgData LENGTH], NULL);
IF( sqlite3_step(UPDATE) == SQLITE_DONE)
{
NSLog(@"已經寫入數據");
}
sqlite3_finalize(UPDATE);
}
}
ELSE
{
NSLog(@"文件不存在");
}
下面代碼從數據庫中讀取圖片二進制數據，然後顯示圖片：
const CHAR * sequel = "select image from test_table where name=?";
sqlite3_stmt * getimg;
IF (sqlite3_prepare_v2(DATABASE, sequel, -1, &getimg, NULL) == SQLITE_OK)
{
CHAR *name = "test";
sqlite3_bind_text(UPDATE, 1, name, -1, NULL);
IF(sqlite3_step(getimg) == SQLITE_ROW)
{
INT bytes = sqlite3_column_bytes(getimg, 0);
Byte * VALUE = (Byte*)sqlite3_column_blob(getimg, 1);
IF (bytes !=0 && VALUE != NULL)
{
NSData * DATA = [NSData dataWithBytes:VALUE LENGTH:bytes];
UIImage * img = [UIImage imageWithData:DATA];
UIImageView * aview =[[UIImageView alloc] initWithFrame:
CGRectMake(0.0, 0.0, IMAGE_WIDTH, IMAGE_HEIGHT)];
aview.image = img;
[SELF.VIEW addSubview:aview];
[aview release];
}
}
sqlite3_finalize(getimg);
}
例2:存儲圖片
/ Save Small Image Data by given main url
- (void) SaveImagesToSql: (NSData*) imgData :(NSString*) mainUrl
{
NSLog( @"n*****Save image to SQLite*****n" );
const char* sqliteQuery = "INSERT INTO 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 from sqlite3_prepare_v2. Error is: %s", sqlite3_errmsg(articlesDB) );
// Finalize and close database.
sqlite3_finalize(statement);
}
讀取圖片:
// Load images from data base with given image url
- (NSData*) LoadImagesFromSql: (NSString*) imageLink
{
NSData* data = nil;
NSString* sqliteQuery = [NSString stringWithFormat:@"SELECT IMAGE FROM IMAGES WHERE 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 and close database.
sqlite3_finalize(statement);
return data;
}
