我正在尝试使用xamarin表单创建一个应用程序,从bittrex获取信息,然后将其放入模型中,然后将其保存到本地SQLite数据库。
以下是我将数据保存到数据库的代码:
public class CoinsDatabase
{
readonly SQLiteAsyncConnection database;
public CoinsDatabase(string dbPath)
{
database = new SQLiteAsyncConnection(dbPath);
database.CreateTableAsync<Coins>().Wait();
}
public Task<List<Coins>> GetCoinsAsync()
{
return database.Table<Coins>().ToListAsync();
}
public Task<Coins> GetCoinsAsync(int id)
{
return database.Table<Coins>().Where(i => i.CoinID == id).FirstOrDefaultAsync();
}
public Task<int> SaveCoinAsync(Coins coin)
{
if(coin.CoinID == 0){
return database.InsertAsync(coin);
} else {
return database.UpdateAsync(coin);
}
}
public Task<int> DeleteCoinAsync(Coins coin)
{
return database.DeleteAsync(coin);
}
以下是获取Json信息并进行处理的代码:
async void Save_Clicked(object sender, System.EventArgs e)
{
if (CoinNameEntry.Text != null){
var uri = new Uri("https://bittrex.com/api/v1.1/public/getmarketsummary?market=btc-" + CoinNameEntry.Text.ToLower());
HttpClient httpClient = new HttpClient();
var response = await httpClient.GetAsync(uri);
if (response.IsSuccessStatusCode)
{
var content = await response.Content.ReadAsStringAsync();
Coins coins = JsonConvert.DeserializeObject<Coin>(content);
var coinItem = (Coins)coins["result"].ToObject<Coins>();
await App.Database.SaveCoinAsync(coinItem);
await Navigation.PopAsync();
} else {
await DisplayAlert("Alert", "An error occured getting the coininformation of " + CoinNameEntry.Text.ToUpper(), "OK");
}
} else {
await DisplayAlert("Alert", "Please select a Coin first", "OK");
}
}
这是我的钱币模型:
public class Coins
{
public List<Coin> coins { get; set; }
}
public class Coin
{
[PrimaryKey, AutoIncrement]
public int CoinID { get; set; }
public string CoinName { get; set; }
public bool Notification { get; set; }
public string MarketName { get; set; }
public double High { get; set; }
public double Low { get; set; }
public double Volume { get; set; }
public double Last { get; set; }
public double BaseVolume { get; set; }
public bool TimeStamp { get; set; }
public double Bid { get; set; }
public double Ask { get; set; }
public int OpenBuyOrders { get; set; }
public int OpenSellOrders { get; set; }
public double PrevDay { get; set; }
public string Created { get; set; }
}
我一直试图让这个工作一个星期了,我想知道是否有人知道我做错了什么,或者是否有人有关于如何解决这个问题的提示。
请记住,我是xamarin和C#的初学者:)
答案 0 :(得分:2)
好的,试试这个:首先,在您的硬币类中添加JsonProperty
,将结果映射到正确的属性:
public class Coins
{
[JsonProperty("result")]
public List<Coin> coins { get; set; }
}
然后在代码中替换以下两行:
Coins coins = JsonConvert.DeserializeObject<Coin>(content);
var coinItem = (Coins)coins["result"].ToObject<Coins>();
与
Coins coins = JsonConvert.DeserializeObject<Coins>(content);
var coinItem = coins.coins[0];
请注意,这将为您提供列表中的第一个硬币 - 如果您想从列表中的其他位置检索硬币,请更改索引或使用LINQ。
我也非常怀疑你的SQLite代码不会做你想要的。目前,所有方法都作用于Coins对象而不是Coin对象。尝试将方法更改为
readonly SQLiteAsyncConnection database;
public CoinsDatabase(string dbPath)
{
database = new SQLiteAsyncConnection(dbPath);
database.CreateTableAsync<Coin>().Wait();
}
public Task<List<Coin>> GetCoinsAsync()
{
return database.Table<Coin>().ToListAsync();
}
public Task<Coin> GetCoinsAsync(int id)
{
return database.Table<Coin>().Where(i => i.CoinID == id).FirstOrDefaultAsync();
}
public Task<int> SaveCoinAsync(Coin coin)
{
if(coin.CoinID == 0){
return database.InsertAsync(coin);
} else {
return database.UpdateAsync(coin);
}
}
public Task<int> DeleteCoinAsync(Coin coin)
{
return database.DeleteAsync(coin);
}