首先,我将一张图片转换为
NSData
格式,并借助于fmdb(flying meat database)以sqlite二进制大对象(blob)的形式插入到数据库中。
然后,我取回NSData数据,但在将NSData转换成UIImage时出现了错误,报错信息为"fatal error: unexpectedly found nil while unwrapping an Optional value
"。
这是我遇到的错误截图:。 var imageData = String()
let countryDB = FMDatabase(path: databasePath as String )
if countryDB.open() {
let querySQL = "SELECT USERIMAGE FROM USERINFO WHERE ID = \((1))"
let results:FMResultSet? = countryDB.executeQuery(querySQL,
withArgumentsInArray: nil)
if results?.next() == true
{
let correctPicture = (results?.dataForColumn("USERIMAGE"))!
print(correctPicture)
let memberPiC : UIImage = UIImage(data: correctPicture)!
print(memberPiC)
} else {
print("record not found")
}
countryDB.close()
} else {
print("Error: \(countryDB.lastErrorMessage())")
}
这是我用来保存图片的代码
func saveData()
{
var data = NSData()
let contactDB = FMDatabase(path : databasePath as String)
let image = UIImage(named: "back.png")
print(image)
if let unwrappedImage = image {
data = UIImageJPEGRepresentation(unwrappedImage, 1.0)!
print("data" , data)
if contactDB.open()
{
let insertQuery = "INSERT INTO USERINFO( userimage) VALUES('\((data))')"
let result = contactDB.executeUpdate(insertQuery, withArgumentsInArray: nil)
if !result {
print("Error: \(contactDB.lastErrorMessage())")
} else {
}
}
else {
print("Error: \(contactDB.lastErrorMessage())")
}
}
}
UIImage
无法使用correctPicture
进行初始化,而由于!
的作用导致崩溃。可以推断出correctPicture
的数据无法转换为UIImage
。 - olympia