Converting sqlite3_column_blob to NSString - ios
I have been trying to add sqlite3_column_blob type of value to NSString by this lines of code :
NSUInteger len = sqlite3_column_bytes(compiledStatement, n);
NSData *cData = [[NSData alloc] initWithBytes:sqlite3_column_blob(compiledStatement, n) length:len];
NSString *columnText = [NSString stringWithUTF8String:[cData bytes]];
Here is the BLOB data which i am trying to retrieve from the database :
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But every time i am getting nil response although there is a value exist. Rest of the parameter values are coming just i am getting nil response in above value.
Thanks.
The reason you cannot convert that data to a string is because it's a PNG image file:
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(I assume; I haven't looked at the PNG spec to confirm this, it's just an assumption at this stage).
Finally i got the solution for the above issue which i was facing :
NSData *content = [[NSData alloc] initWithBytes:sqlite3_column_blob(compiledStatement, 2) length:sqlite3_column_bytes(compiledStatement, 2)];
NSString *columnText = [content base64EncodedStringWithOptions:NSDataBase64Encoding64CharacterLineLength];
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