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Classes Questionping and I Questionpin are same , but still I get error saying cannot implicitlyconvert Questionping to IQuestionpin
@inject NavigationManager Navigation
@using System.Text;
@using System.Net.Http.Headers;
@using Microsoft.AspNetCore.Components;
@using Newtonsoft.Json;
@using Microsoft.JSInterop;
@using MauiAppMCQs.Models;
@page "/Login"
<h3>Login</h3>
<EditForm Model="@submitActivity" OnSubmit="@Submit">
<br />
<div class="row">
<div class="col-md-3">
<p>PIN</p>
</div>
<div class="col-md-4">
<input placeholder="PIN" @bind="@pin" />
</div>
</div>
<div>
<button type="submit">Submit</button>
</div>
<div>
@errmsg
</div>
</EditForm>
@code {
private int pin; private string jwttoken; private string connected; private string jsonString;
public string @errmsg = "";
private ACTIVITY submitActivity { get; set; } = new();
List<Questionpin> Questions = new List<Questionpin>();
List<IQuestionpin> OQuestions = new List<IQuestionpin>();
List<Questionpin> res;
QuestionsDatabasepin questionsDatabasepin;
public class Questionpin
{
public long Id { get; set; }
public int Pinnum { get; set; }
}
public string matches;
public class ACTIVITY
{
public string Dummy { get; set; }
}
private async void Submit()
{
questionsDatabasepin = new QuestionsDatabasepin();
// Questions = list1;
LoadQuestionsAsync();
// Questions = list1;
var result = Questions.FirstOrDefault(c => c.Pinnum == pin);
if (result == null)
{
errmsg = "Enter Valid pin";
}
else
{ Navigation.NavigateTo("/NewNav", true); }
}
private async void LoadQuestionsAsync()
{ res = await GetApiData(); }
async Task<List<Questionpin>> GetApiData()
{
var jsonContent = new StringContent(JsonConvert.SerializeObject(new
{
bodyField1 = ""
}), Encoding.UTF8, "application/json");
connected = "N";
try
{
using (var client1 = new HttpClient())
{
string authurl = "https://myquizapi.azurewebsites.net/api/";
client1.BaseAddress = new Uri(authurl);
client1.DefaultRequestHeaders.Clear();
client1.DefaultRequestHeaders.Accept.Add(new MediaTypeWithQualityHeaderValue("application/json"));
HttpResponseMessage Res = await client1.PostAsync("Auth", jsonContent);
if (Res.IsSuccessStatusCode)
{
//Storing the response details recieved from web api
string json = await Res.Content.ReadAsStringAsync();
// Parse the JSON response to extract the address
dynamic data1 = Newtonsoft.Json.JsonConvert.DeserializeObject(json);
jwttoken = data1.token;
}
}
string apiUrl = "https://myquizapi.azurewebsites.net/api/";
using (HttpClient client = new HttpClient())
{
client.BaseAddress = new Uri(apiUrl);
client.DefaultRequestHeaders.Clear();
client.DefaultRequestHeaders.Accept.Add(new MediaTypeWithQualityHeaderValue("application/json"));
client.DefaultRequestHeaders.Add("Authorization", $"Bearer {jwttoken}");
HttpResponseMessage response = null;
response = await client.GetAsync("pins");
// Check if the request was successful (status code 200)
if (response.IsSuccessStatusCode)
{
// Make a GET request to the API
connected = "Y";
// Read the content of the response
string jsonString = await response.Content.ReadAsStringAsync();
List<IQuestionpin> itemInTheDB = await questionsDatabasepin.GetItemsAsync();
// Deserialize the JSON string into an object
Questions = JsonConvert.DeserializeObject<List<Questionpin>>(jsonString);
foreach (IQuestionpin item in itemInTheDB)
{
var result = Questions.FirstOrDefault(c => c.Id == item.Id);
if (result == null)
{
await questionsDatabasepin.DeleteItemAsync(item);
}
}
OQuestions = JsonConvert.DeserializeObject<List<IQuestionpin>>(jsonString);
List<IQuestionpin> itemOutTheDB = OQuestions;
foreach (IQuestionpin itemdb in itemOutTheDB)
{
var resulty = itemInTheDB.FirstOrDefault(c => c.Id == itemdb.Id);
matches = "N";
if (resulty == null)
{ await questionsDatabasepin.SaveItemAsync(itemdb); }
if (resulty != null)
{
if ((resulty.Id == itemdb.Id) && (resulty.Pinnum == itemdb.Pinnum) )
{ matches = "Y"; }
}
else
{ await questionsDatabasepin.SaveItemAsync(itemdb); }
if (matches == "N")
{ await questionsDatabasepin.SaveItemAsync(itemdb); }
}
}
else { OQuestions = await questionsDatabasepin.GetItemsAsync();
Questions = OQuestions;
}
}
}
catch (Exception ex)
{
if (connected == "N")
{
OQuestions = await questionsDatabasepin.GetItemsAsync();
Questions = OQuestions;
}
}
return Questions; }
}
using SQLite;
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
namespace MauiAppMCQs.Models
{
public class QuestionsDatabasepin
{
SQLiteAsyncConnection Database;
private SQLiteAsyncConnection _dbConnection;
public const string DatabaseFilename = "MCQpin.db3";
async Task Init()
{
string dbPath =
Path.Combine(FileSystem.AppDataDirectory, DatabaseFilename);
FileStream fileStream = new FileStream(dbPath, FileMode.OpenOrCreate, FileAccess.ReadWrite, FileShare.ReadWrite);
_dbConnection = new SQLiteAsyncConnection(dbPath);
if (Database is not null)
return;
Database = new SQLiteAsyncConnection(dbPath, Constants.Flags);
var result = await Database.CreateTableAsync<IQuestionpin>();
}
public async Task<List<IQuestionpin>> GetItemsAsync()
{
await Init();
var res = await Database.Table<IQuestionpin>().ToListAsync();
return res;
}
public async Task<IQuestionpin> GetItemAsync(long id)
{
await Init();
return await Database.Table<IQuestionpin>().Where(i => i.Id== id).FirstOrDefaultAsync();
}
public async Task<long> SaveItemAsync(IQuestionpin item)
{
await Init();
IQuestionpin res = await GetItemAsync(item.Id);
if (res != null)
return await Database.UpdateAsync(item);
else
return await Database.InsertAsync(item);
}
public async Task<int> DeleteItemAsync(IQuestionpin item)
{
await Init();
return await Database.DeleteAsync(item);
}
}
}
namespace MauiAppMCQs.Models
{
public class IQuestionpin
{
[PrimaryKey, Indexed]
public long Id { get; set; }
public int Pinnum { get; set; }
}
}
Classes Questionping and I Questionpin are same ,
The classes defintions "look similar", but are far away from beeing the same. Even the case of ID/Id are different.
You have to write an explict conversion.
I made the classes same still I get the compilations error
I am getting error in
Questions = OQuestions;
I tried this it doesnt work
foreach (IQuestionpin itemdb in OQuestions)
{
Questions.Add(new Questionpin(itemdb.Id, itemdb.Pinnum));
}
public class IQuestionpin
{
[PrimaryKey, Indexed]
public long Id { get; set; }
public int Pinnum { get; set; }
}
``` public class Questionpin
```java
{
public long Id { get; set; }
public int Pinnum { get; set; }
}
![](data:image/svg+xml, %3Csvg xmlns='http://www.w3.org/2000/svg' height='64' class='font-weight-bold' style='font: 600 30.11764705882353px "SegoeUI", Arial' width='64'%3E%3Ccircle fill='hsl(211.20000000000002, 61%, 30%)' cx='32' cy='32' r='32' /%3E%3Ctext x='50%25' y='55%25' dominant-baseline='middle' text-anchor='middle' fill='%23FFF' %3EBS%3C/text%3E%3C/svg%3E)
they are not the same. they just have similar properties.
you can only cast one class to another one inherits of the other. if both classes had the same interface you could cast by interface. to be able to cast Questionpin to IQuestionpin they need to be defined:
inheritance:
public class Questionpin
{
public long Id { get; set; }
public int Pinnum { get; set; }
}
public class IQuestionpin : Questionpin
{
[PrimaryKey, Indexed]
public override long Id { get; set; }
}
...
var list = new List<Questionpin>();
var q1 = new IQuestionpin {...};
var list.Add(q1);
interface:
public interface QuestionpinInterface
{
long Id { get; set; }
int Pinnum { get; set; }
}
public class Questionpin : QuestionpinInterface
{
public long Id { get; set; }
public int Pinnum { get; set; }
}
public class IQuestionpin : QuestionpinInterface
{
[PrimaryKey, Indexed]
public long Id { get; set; }
public int Pinnum { get; set; }
}
...
var list = new List<QuestionpinInterface>();
var q1 = new IQuestionpin {...};
var list.Add(q1);
but a better approach is a mapper
public class Questionpin
{
public long Id { get; set; }
public int Pinnum { get; set; }
}
public class IQuestionpin
{
[PrimaryKey, Indexed]
public long Id { get; set; }
public int Pinnum { get; set; }
}
public static class QuestionpinMappers
{
public static Questionpin MapToQuestionpin(this IQuestionpin source) => new Questionpin
{
Id = source.Id,
Pinnum = source.Pinnum
};
}
...
var list = new List<Questionpin>();
var q1 = new IQuestionpin {...};
var list.Add(q1.MapToQuestionpin());
I converted using this
OQuestions = await questionsDatabasepin.GetItemsAsync();
foreach (IQuestionpin itemdb in OQuestions)
{
Questions.Add(new Questionpin { Id = itemdb.Id, Pinnum = itemdb.Pinnum });
}
@inject NavigationManager Navigation
@using System.Text;
@using System.Net.Http.Headers;
@using Microsoft.AspNetCore.Components;
@using Newtonsoft.Json;
@using Microsoft.JSInterop;
@using MauiAppMCQs.Models;
@page "/Login"
<h3>Login</h3>
<EditForm Model="@submitActivity" OnSubmit="@Submit">
<br />
<div class="row">
<div class="col-md-3">
<p>PIN</p>
</div>
<div class="col-md-4">
<input placeholder="PIN" @bind="@pin" />
</div>
</div>
<div>
<button type="submit">Submit</button>
</div>
<div>
@errmsg
</div>
</EditForm>
@code {
private int pin; private string jwttoken; private string connected; private string jsonString;
public string @errmsg = "";
private ACTIVITY submitActivity { get; set; } = new();
List<Questionpin> Questions = new List<Questionpin>();
List<IQuestionpin> OQuestions = new List<IQuestionpin>();
List<Questionpin> res;
QuestionsDatabasepin questionsDatabasepin;
public class Questionpin
{
public long Id { get; set; }
public int Pinnum { get; set; }
}
public string matches;
public class ACTIVITY
{
public string Dummy { get; set; }
}
private async void Submit()
{
questionsDatabasepin = new QuestionsDatabasepin();
// Questions = list1;
LoadQuestionsAsync();
// Questions = list1;
var result = Questions.FirstOrDefault(c => c.Pinnum == pin);
if (result == null)
{
errmsg = "Enter Valid pin";
}
else
{ Navigation.NavigateTo("/NewNav", true); }
}
private async void LoadQuestionsAsync()
{ res = await GetApiData(); }
async Task<List<Questionpin>> GetApiData()
{
var jsonContent = new StringContent(JsonConvert.SerializeObject(new
{
bodyField1 = ""
}), Encoding.UTF8, "application/json");
connected = "N";
try
{
using (var client1 = new HttpClient())
{
string authurl = "https://myquizapi.azurewebsites.net/api/";
client1.BaseAddress = new Uri(authurl);
client1.DefaultRequestHeaders.Clear();
client1.DefaultRequestHeaders.Accept.Add(new MediaTypeWithQualityHeaderValue("application/json"));
HttpResponseMessage Res = await client1.PostAsync("Auth", jsonContent);
if (Res.IsSuccessStatusCode)
{
//Storing the response details recieved from web api
string json = await Res.Content.ReadAsStringAsync();
// Parse the JSON response to extract the address
dynamic data1 = Newtonsoft.Json.JsonConvert.DeserializeObject(json);
jwttoken = data1.token;
}
}
string apiUrl = "https://myquizapi.azurewebsites.net/api/";
using (HttpClient client = new HttpClient())
{
client.BaseAddress = new Uri(apiUrl);
client.DefaultRequestHeaders.Clear();
client.DefaultRequestHeaders.Accept.Add(new MediaTypeWithQualityHeaderValue("application/json"));
client.DefaultRequestHeaders.Add("Authorization", $"Bearer {jwttoken}");
HttpResponseMessage response = null;
response = await client.GetAsync("pins");
// Check if the request was successful (status code 200)
if (response.IsSuccessStatusCode)
{
// Make a GET request to the API
connected = "Y";
// Read the content of the response
string jsonString = await response.Content.ReadAsStringAsync();
List<IQuestionpin> itemInTheDB = await questionsDatabasepin.GetItemsAsync();
// Deserialize the JSON string into an object
Questions = JsonConvert.DeserializeObject<List<Questionpin>>(jsonString);
foreach (IQuestionpin item in itemInTheDB)
{
var result = Questions.FirstOrDefault(c => c.Id == item.Id);
if (result == null)
{
await questionsDatabasepin.DeleteItemAsync(item);
}
}
OQuestions = JsonConvert.DeserializeObject<List<IQuestionpin>>(jsonString);
List<IQuestionpin> itemOutTheDB = OQuestions;
foreach (IQuestionpin itemdb in itemOutTheDB)
{
var resulty = itemInTheDB.FirstOrDefault(c => c.Id == itemdb.Id);
matches = "N";
if (resulty == null)
{ await questionsDatabasepin.SaveItemAsync(itemdb); }
if (resulty != null)
{
if ((resulty.Id == itemdb.Id) && (resulty.Pinnum == itemdb.Pinnum) )
{ matches = "Y"; }
}
else
{ await questionsDatabasepin.SaveItemAsync(itemdb); }
if (matches == "N")
{ await questionsDatabasepin.SaveItemAsync(itemdb); }
}
}
else { OQuestions = await questionsDatabasepin.GetItemsAsync();
// Questions = OQuestions;
foreach (IQuestionpin itemdb in OQuestions)
{
Questions.Add(new Questionpin { Id = itemdb.Id, Pinnum = itemdb.Pinnum });
}
}
}
}
catch (Exception ex)
{
if (connected == "N")
{
OQuestions = await questionsDatabasepin.GetItemsAsync();
foreach (IQuestionpin itemdb in OQuestions)
{
Questions.Add(new Questionpin { Id = itemdb.Id, Pinnum = itemdb.Pinnum });
}
}
}
return Questions; }
}