How to Check if a database exists in SQLite?

Question

I am developing a windows phone 8 app using sqlite and am trying to check if the database exists and if it doesnt exist,it should be created. but i keep getting the error message "System.windows.shapes.path does not contain a definition for combine". Is there another way to do it or how can i improve it?

public static string DB_PATH = Path.Combine(Path.Combine(ApplicationData.Current.LocalFolder.Path, "ContactsManager.sqlite"));//DataBase Name 
    public App()
    {
        if (!CheckFileExists("ContactsManager.sqlite").Result)
        {
            using (var db = new SQLiteConnection(DB_PATH))
            {
                db.CreateTable<Contacts>();
            }
        }
    }

    private async Task<bool> CheckFileExists(string fileName)
    {
        try
        {
            var store = await Windows.Storage.ApplicationData.Current.LocalFolder.GetFileAsync(fileName);
            return true;
        }
        catch
        {
        }
        return false;
    }

Path.Combine is defined in System.IO.Path.

Panagiotis Kanavos
– Panagiotis Kanavos

2015-09-11 13:37:55 +00:00
Commented Sep 11, 2015 at 13:37 — Panagiotis Kanavos
– Panagiotis Kanavos, Commented Sep 11, 2015 at 13:37

Sources · Accepted Answer · 2015-09-11 14:27:05Z

2

Do you really need to check if the database exist? I don't know about windows phone, but in Windows, as soon as you try to add a table into a SQLite database, if the database doesn't exist, it creates it. If you are worried about the table existing already, you can use:

CREATE TABLE IF NOT EXISTS tableName(...)

(I tried to ask it as comment but I don't have the reputation)

answered Sep 11, 2015 at 14:27

Sources

211 silver badge3 bronze badges

Sign up to request clarification or add additional context in comments.

Comments

BendEg · Accepted Answer · 2015-09-11 13:27:01Z

1

Why do you have a Path.Combine in a Path.Combine? If Path.Combine is not available with one or two parameter, why not simple concat two strings?

You have it 2x: public static string DB_PATH = Path.Combine(Path.Combine(ApplicationData.Current.LocalFolder.Path, "ContactsManager.sqlite"));

answered Sep 11, 2015 at 13:27

BendEg

21.3k17 gold badges69 silver badges135 bronze badges

6 Comments

Panagiotis Kanavos Over a year ago

Path.Combine does accept two parameters. It's either a typo or copy pasted code on the OP's part

BendEg Over a year ago

It also could be his problem, because the compiler say: System.windows.shapes.path does not contain a definition for combine or am i wrong?

BendEg Over a year ago

maybe i am blind but the method with one string parameter (msdn.microsoft.com/de-de/library/dd991142(v=vs.110).aspx) is available since windows phone 8.1

Panagiotis Kanavos Over a year ago

Wrong. Path.Combine is in the System.IO.Path class. You probably added the wrong reference

BendEg Over a year ago

Yep totally wrong. my fault. i will delete the answer

|

user5308950 · Accepted Answer · 2015-09-11 13:30:09Z

1

you can check by this:

public async Task<bool> isFilePresent(string fileName)
 {
 return System.IO.File.Exists(string.Format(@"{0}\{1}", ApplicationData.Current.LocalFolder.Path, fileName);
 }

answered Sep 11, 2015 at 13:30

user5308950

Comments

Nishchith Uchil · Accepted Answer · 2015-09-11 19:05:30Z

0

@Panagiotis Kanavos's comment was right, you have resolved the Path class using wrong namespace!

Remove

using System.Windows.Shapes; // for silverlite
using Windows.UI.Xaml.Shapes; // for winrt

and add

using System.IO;

answered Sep 11, 2015 at 19:05

Nishchith Uchil

1521 gold badge1 silver badge14 bronze badges

1 Comment

Leonard Kanyesigye Over a year ago

thank you...it worked perfect.. i removed using System.windows.shapes and replaced it with using System.IO

Collectives™ on Stack Overflow

How to Check if a database exists in SQLite?

4 Answers 4

Comments

6 Comments

Comments

1 Comment

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

4 Answers 4

Comments

6 Comments

Comments

1 Comment

Your Answer

Sign up or log in

Post as a guest

Related