My problem is that I'm using the CreateTableAsync method and is always returning "0". I researched and saw that this return is a mistake.
I wanted to know what I'm doing wrong.
Class Service Table:
public class SqliteTable
{
private readonly SqliteWrapper _sqliteWrapper;
public SqliteTable()
{
_sqliteWrapper = new SqliteWrapper();
}
private async Task<bool> CheckIfExistTable<T>() where T : new()
{
var connection = _sqliteWrapper.OpenDatabase();
try
{
var result = await connection.Table<T>().CountAsync();
return result.Equals(0);
}
catch (Exception e)
{
Logs.Logs.Error($"Error get count table {typeof(T).Name}: {e.Message}");
return false;
}
}
public async void CreateTable<T>() where T : new()
{
var connection = _sqliteWrapper.OpenDatabase();
if (await CheckIfExistTable<T>())
{
Logs.Logs.Info($"This table {typeof(T).Name} was created");
return;
}
var createTableResult = await connection.CreateTableAsync<T>();
var value = createTableResult.Results.Values.FirstOrDefault();
if (value.Equals(1))
{
Logs.Logs.Info($"Create table {typeof(T).Name}");
}
else
{
throw new Exception($"Error create table {typeof(T).Name}");
}
}
}
I create a Class Model Login. which would be the object to create the database.
public class Login
{
public Login()
{
}
public Login(string user, string password)
{
User = user;
Password = password;
}
public Login(int id, string user, string password)
{
Id = id;
User = user;
Password = password;
}
[PrimaryKey, AutoIncrement, Column("login_id")]
public int Id { get; set; }
[Unique, NotNull, Column("login_user")]
public string User { get; set; }
[NotNull, Column("login_password")] public string Password { get; set; }
}
I create Class CreateTableAsync. Which would be to intanciar the SqliteTable, to call the method CreateTable sending the object to create the database:
protected override void OnStart()
{
try
{
var sqliteTable = new SqliteTable();
sqliteTable.CreateTable<Login>();
}
catch (Exception e)
{
Logs.Logs.Error($"Error init application: {e.Message}");
}
}
Can someone help me?
Related
So my code works in PostMan querying the api to populate a listview locally in my Android app. But when I run it from within the app, I get NullReferenceException on the line "Items.Clear() in ShipViewModel.cs
I tried hardcoding the address rather than using my APIQueriable path, I tried generating new JWT, and I tried manually cleaning my /bin /obj folders to rule out code not compiling correctly.
ShipsViewModel.cs Xamarin.Forms/ViewModels
{
private GallogClient _gallogClient;
public ObservableCollection<ShipCatalog> Items { get; set; }
public Command LoadItemsCommand { get; }
public ShipsViewModel()
{
Title = "Ships";
_gallogClient = new GallogClient("eyJ0eXAiOiJKV1QiLCJhbGciOiJIUzI1NiJ9.eyJpc3MiOiJodHRwOlwvXC9hcGkuZ2FsbG9nLmNvIiwiYXVkIjoiaHR0cDpcL1wvYXBpLmdhbGxvZy5jbyIsImlhdCI6MTM1Njk5OTUyNCwibmJmIjoxMzU3MDAwMDAwLCJkYXRhIjp7ImlkIjo1NywidXNlcm5hbWUiOiJQYXJhIiwiaGFuZGxlIjoiUGFyYSIsImVtYWlsIjoicGFyYWJvbGE5NDlAZ21haWwuY29tIn19.bRpI9hVy-Spky5pbZhJCkyN-MT9RA6ap_yD9ezRxCxo");
LoadItemsCommand = new Command(async () => await ExecuteLoadItemsCommand(), () => !IsBusy);
}
async Task ExecuteLoadItemsCommand()
{
if (IsBusy)
return;
IsBusy = true;
try
{
LoadItemsCommand.ChangeCanExecute();
Items.Clear();
var items = await _gallogClient.GetItemsAsync<ShipList>();
foreach (var item in items.ships.ToList())
{
Items.Add(item);
}
}
catch (Exception ex)
{
Debug.WriteLine(ex);
}
finally
{
IsBusy = false;
}
}
}
}
GallogClient.cs Gallog.API
{
internal readonly HttpClient Client = new HttpClient { BaseAddress = new Uri("https://api.gallog.co/api/") };
public string Jwt { get; set; }
public GallogClient()
{
}
public GallogClient(string jwt)
{
Jwt = jwt;
}
private StringContent JwtContent
{
get {
return new StringContent(JsonConvert.SerializeObject(new
{
jwt = Jwt
}), Encoding.UTF8, "application/json");
}
}
//...
public async Task<T> GetItemAsync<T>(string name) where T : ApiQueryable
{
return await PostAsync<T>($"{GetPath<T>()}/{name}");
}
public async Task<T> GetItemsAsync<T>() where T : ApiQueryable
{
return await PostAsync<T>($"{GetPath<T>()}");
}
internal string GetPath<T>()
{
if (typeof(T).GetCustomAttributes(
typeof(ApiPathAttribute), true
).FirstOrDefault() is ApiPathAttribute at)
{
return at.Path;
}
return null;
}
public async Task<T> PostAsync<T>(string path) where T : ApiQueryable
{
var response = await Client.PostAsync(path, JwtContent);
return JsonConvert.DeserializeObject<T>(await response.Content.ReadAsStringAsync());
}
public async Task<T> PostAsync<T>(object body, string path) where T : ApiQueryable
{
var response = await Client.PostAsync(path,
new StringContent(JsonConvert.SerializeObject(body), Encoding.UTF8, "application/json"));
return JsonConvert.DeserializeObject<T>(await response.Content.ReadAsStringAsync());
}
}
}
ShipList.cs Xamarin.Forms/Models
{
[ApiPath("ships")]
public class ShipList : ApiQueryable
{
public ShipCatalog[] ships { get; set; }
}
public class ShipCatalog
{
public int id { get; set; }
public string name { get; set; }
// ...etc etc
}
}
Items is null because you declared it but have never initialized it
public ShipsViewModel()
{
...
Items = new ObservableCollection<ShipCatalog>();
...
}
I'm trying to store some information as a class instance in a SQLite table. The instances need to be unique in their DateTime property. I'm completely new to database programming, and I don't really understand how use SQLite in Xamarin. As new instances are created they need to update the existing instances in the table if they match in their DateTime property.
SQLiteAsyncConnection connection = new SQLiteAsyncConnection(App.FilePath);
await connection.CreateTableAsync<ModulInformationData>();
ModulInformationData data = new ModulInformationData();
data.InitModulInformation(modul);
int rows = 0;
try
{
rows = await connection.UpdateAsync(data);
}catch(Exception e)
{
Console.WriteLine("SQL Update failed " + e.Message);
}
Console.WriteLine("rows updated: " + rows);
if (rows == 0)
{
Console.WriteLine("before insert");
try
{
int key1 = await connection.InsertAsync(data);
Console.WriteLine("after insert: " + key1);
}catch (Exception e)
{
Console.WriteLine("SQL insert failed " + e.Message);
}
}
The ModulInformationData class
public class ModulInformationData
{
[PrimaryKey,AutoIncrement]
public int Id { get; set; }
[Unique]
public DateTime tidspunkt { get; set; }
other properties...
At the moment, I'm catching an error when inserting, but the message only says 'Constraint'. What can I do to make this work?
Do you want to achieve the result like this GIF。
First of all, you can create a class for the database CRUD.
public class NoteDatabase
{
readonly SQLiteAsyncConnection _database;
public NoteDatabase(string dbPath)
{
_database = new SQLiteAsyncConnection(dbPath);
_database.CreateTableAsync<Note>().Wait();
}
public Task<List<Note>> GetNotesAsync()
{
return _database.Table<Note>().ToListAsync();
}
public Task<Note> GetNoteAsync(int id)
{
return _database.Table<Note>()
.Where(i => i.ID == id)
.FirstOrDefaultAsync();
}
public Task<int> SaveNoteAsync(Note note)
{
if (note.ID != 0)
{
return _database.UpdateAsync(note);
}
else
{
return _database.InsertAsync(note);
}
}
public Task<int> DeleteNoteAsync(Note note)
{
return _database.DeleteAsync(note);
}
}
Then there is model class.
public class Note
{
[PrimaryKey, AutoIncrement]
public int ID { get; set; }
public string Text { get; set; }
[Unique]
public DateTime Date { get; set; }
public string Gender { get; set; }
}
If we want to add or update the data to the database, firstly, we should update the data to the instance, then we could just save this instance to the database like following save click event.
async void OnSaveButtonClicked(object sender, EventArgs e)
{
var note = (Note)BindingContext;
note.Date = DateTime.UtcNow;
note.Gender = (string)myPicker.SelectedItem;
await App.Database.SaveNoteAsync(note);
await Navigation.PopAsync();
}
Here is my demo. you can download it and refer to it.
https://github.com/851265601/databaseDemo
I have created this typefilter that is supposed to take 2 variables in order for it to send to a method that is linked to the filter. However, I am unable to attach my 2 variables for it to run.
public class RolesFilterAttribute : TypeFilterAttribute
{
public RolesFilterAttribute() : base(typeof(RolesFilterAttributeImpl))
{
}
private class RolesFilterAttributeImpl : IActionFilter
{
private readonly ValidateRoleClient validateRoleClient;
private string Role;
private string SecretKey;
public RolesFilterAttributeImpl(string Role, string SecretKey, ValidateRoleClient validateRoleClient)
{
this.validateRoleClient = validateRoleClient;
this.Role = Role;
this.SecretKey = SecretKey;
}
public void OnActionExecuted(ActionExecutedContext context)
{
if (context.HttpContext.Request.Cookies["Token"] != null || context.HttpContext.Request.Cookies["RefreshToken"] != null)
{
TokenViewModel tvm = new TokenViewModel
{
Token = context.HttpContext.Request.Cookies["Token"],
RefreshToken = context.HttpContext.Request.Cookies["RefreshToken"]
};
ValidateRoleViewModel vrvm = new ValidateRoleViewModel
{
Role = Role,
SecretKey = SecretKey,
Token = tvm
};
validateRoleClient.ValidateRole(vrvm);
}
}
public void OnActionExecuting(ActionExecutingContext context)
{
throw new NotImplementedException();
}
}
}
This is how I declare the filter and it compiles fine. However, I am not able to pass the required variables which are SecretKey and Role through it. Is my typefilter declared correctly?
[TypeFilter(typeof(RolesFilterAttribute))]
public IActionResult About()
{
return View();
}
Taken from the official documentation
[TypeFilter(typeof(AddHeaderAttribute),
Arguments = new object[] { "Author", "Steve Smith (#ardalis)" })]
public IActionResult Hi(string name)
{
return Content($"Hi {name}");
}
I have tried to send data as a string and it is working correctly. but now i want to insert all gridview data as a list into database. Code is here
public interface IService1
{
[OperationContract]
string InsertCustomerDetails(UserDetails userInfo);
[OperationContract]
[WebGet]
List<CustomerTable> GetCustomers();
}
public class UserDetails
{
string Name = string.Empty;
string City = string.Empty;
[DataMember]
public string name
{
get { return Name; }
set { Name = value; }
}
[DataMember]
public string city
{
get { return City; }
set { City = value; }
}
public class Service1 : IService1
{
public string InsertCustomerDetails(UserDetails userInfo)
{
using(DataContext db=new DataContext())
{
CustomerTable customer = new CustomerTable();
customer.Name = userInfo.name;
customer.City = userInfo.city;
db.CustomerTables.Add(customer);
db.SaveChanges();
}
return "name= " + userInfo.name + " city= " + userInfo.city;
}
}
}
WEB Form Code
protected void ButtonADD_Click(object sender, EventArgs e)
{
for (int i = 0; i < GridView2.Rows.Count; i++) {
UserDetails info = new UserDetails();
info.name = GridView2.Rows[i].Cells[0].Text;
info.city = GridView2.Rows[i].Cells[1].Text;
obj.InsertCustomerDetails(info);
} }
In Iservice1 class use this
public List<CustomerTable> InsertCustomerDetails(UserDetails userInfo)
{
using(DataContext db=new DataContext())
{
CustomerTable customer = new CustomerTable();
customer.Name = userInfo.name;
customer.City = userInfo.city;
db.CustomerTables.Add(customer);
db.SaveChanges();
return db.CustomerTables.ToList();
}
Use this in interface. Make setter getters in class UserDetails
[OperationContract]
List<CustomerTable> InsertCustomerDetails(UserDetails userInfo);
I Have done this. Just facing problem in Web Form. Any Help will be appriciated. I want to send dqata as list into database
This is my first time creating a web service. I am not sure if my implementation is incorrect, but I am trying to use much like a class. The problem is that when I am trying to consume I am getting confused and not being able to set the values of the properties.
here is the web service.
public class Service1 : System.Web.Services.WebService
{
private bool _isUserActive { get; set; }
private bool _isCredentialValid { get; set; }
public string email { get; set; }
public string pass { get; set; }
public int customerID { get; set; }
[WebMethod]
public bool VerifyUserCredential()
{
bool result = false;
PURLDataContext purl = new PURLDataContext();
try
{
var res = purl.Sel_User(email.ToLower(), pass);
if (res != null)
result = true;
_isUserActive = true;
_isCredentialValid = true;
}
catch (Exception ex)
{
if (ex.Message == "Account is inactive, please contact your administrator!")
{
_isUserActive = false;
_isCredentialValid = false;
}
else
_isCredentialValid = false;
//Invalid credentials.
}
return result;
}
[WebMethod]
public ArrayList retrieveCustomerInfo()
{
ArrayList customerInfo = new ArrayList();
string validate = "Please Validate";
if (_isCredentialValid)
{
PURLDataContext purl = new PURLDataContext();
var customer = purl.Sel_Recipient(customerID);
foreach (var c in customer)
{
customerInfo.Add(c);
}
}
else
customerInfo.Add(validate);
return customerInfo;
}
}
Here is what I am trying to do to consume.
PURLServices.Service1SoapClient webserv = new Service1SoapClient();
bool result;
ArrayOfAnyType array = new ArrayOfAnyType();
webserv.email = "email#email.com";
webserv.pass = "pass";
webserv.customerID = 12345;
result = webserv.VerifyUserCredential();
array = webserv.retrieveCustomerInfo();
Thank you for any help/
You do not want to try to use properties like this. Your method should look more like this:
public bool VerifyUserCredential(string userName, string password)
{
// method body here
}
Probably you would want to return an access token of some sort that the server will cache. This can then be passed into other methods to show that the user is valid.