unexpectedly found nil while unwrapping an Optional value while reading from DS with fromCString

Question

I am reading from a dbtable and get an error at a specific position of the table. My sql is ok, because I could already read from the same table, but at a specific row I get an error and I would like to know howto handle this error. I am not looking for a solution to solve my db-issue, I am just looking for handling the error, so it doesn't crash.

I have the following code :

let unsafepointer=UnsafePointer<CChar>(sqlite3_column_text(statement, 2));
if unsafepointer != nil {
    sText=String.fromCString(unsafepointer)! // <<<<<< ERROR
} else {
   sText="unsafe text pointer is nil !";
}

I get an error:

"fatal error: unexpectedly found nil while unwrapping an Optional value"

at line marked with <<<<<< ERROR.

The unsafe pointer's value is not nil:

pointerValue : 2068355072

How can I handle this error, so my app is not crashing ?

ciccioska · Accepted Answer · 2016-05-15T12:50:44.903

3

Another possible solution is this:

let unsafepointer=UnsafePointer<CChar>(sqlite3_column_text(statement, 2));
var sText = "unsafe text pointer is nil !";
if unsafepointer != nil{
    if let text = String.fromCString(unsafepointer) as String?{
        sText = text;
    }    
}

edited May 15 '16 at 12:50

answered May 15 '16 at 12:37

ciccioska

1,291
16
22

I get an syntax error in the if statement "Initializer for conditional binding must have Optional type, not 'UnsafePointer' (aka 'UnsafePointer')" – mcfly soft May 15 '16 at 12:42
Thanks you very much. Helps a lot. – mcfly soft May 15 '16 at 12:53

score 1 · Answer 2 · answered Dec 08 '19 at 18:37

1

if sqlite3_column_text(statement, 2) != nil {                     
print("do something")
} else {
YourString = ""
}

answered Dec 08 '19 at 18:37

Miguel Herrero

39
2

2

Hi Miguel - can you explain why this answer is better than the accepted answer? – stdunbar Dec 08 '19 at 19:49

Alessandro Ornano · Answer 3 · 2016-05-15T12:50:14.637

0

let statementValue = sqlite3_column_text(statement, 2)
var sText = withUnsafeMutablePointer(&statementValue) {UnsafeMutablePointer<Void>($0)}

edited May 15 '16 at 12:50

answered May 15 '16 at 08:44

Alessandro Ornano

34,887
11
106
133

I do not understand. I have still the same problem and in sText, there is no text. sText is a UnsafeMutablePointer. Howto handle the error ? – mcfly soft May 15 '16 at 12:27
What about now? Are you sure do you have a valid statement value? – Alessandro Ornano May 15 '16 at 12:46
I get an syntax error at the "if let ..." statement : "Initializer for conditional binding must have Optional type, not 'UnsafePointer'". I am at Xcode 7.2 – mcfly soft May 15 '16 at 12:48
Thanks for helping. I could use the sample from "ciccioska". – mcfly soft May 15 '16 at 12:53
Can you edit your proposed answer to expand on what this does and how it addresses the OP? – Ro Yo Mi May 15 '16 at 21:06

unexpectedly found nil while unwrapping an Optional value while reading from DS with fromCString

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