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我有一条记录在本地存储在设备上，我有一个按钮可以从本地存储中删除记录。当用户按下按钮时，会调用此方法并从本地设备中删除记录（通过使 guid 无效）。我正在使用 Akavache 来保存数据。

虽然这在大多数情况下都有效，但我注意到有时当我删除记录并刷新视图时，记录会从集合中删除。但是，如果注销并重新登录应用程序，记录会重新出现。

我想知道这是否是在本地存储和删除记录的正确方法？

public async Task RemoveFormFromDevice(FormData form)
{
    string cacheKey = "data." + form.Guid.ToString ();

    await _cache.Invalidate (cacheKey);
    await _localStorage.Invalidate (cacheKey);

    List<KeyValuePair<Guid, int?>> guids = await _cache.Get<List<KeyValuePair<Guid, int?>>>(CACHE_KEY_PROCS);

    if (guids == null)
        return;

    guids.RemoveAll (a => a.Key == form.Guid);

    await _cache.Insert (CACHE_KEY_PROC, guids, null);
    await _localStorage.Insert (CACHE_KEY_PROCS, guids, null);
}

编辑：这是我登录应用程序时检索记录的方式：

private async Task<List<FormData>> getSavedProcs()
{
    List<FormData> forms = new List<FormData> ();

    List<KeyValuePair<Guid, int?>> guids = await _cache.Get<List<KeyValuePair<Guid, int?>>> (CACHE_KEY_PROCS);

    if (guids != null)
    {
        foreach (KeyValuePair<Guid, int?> pair in guids)
        {
            string cacheKey = "data." + pair.Key.ToString ();
            string formJson = await _cache.Get<string> (cacheKey);

            FormData form = JsonConvert.DeserializeObject<FormData> (formJson);
            if (form != null)
                forms.Add (form);
        }
    }
    return forms;
}

public async Task<T> Get<T>(string key) where T : class
{
    try
    {
        return await memoryCache.GetObject<T> (key);
    }
    catch(KeyNotFoundException ex) {
        T localStoreObj = await localStorage.Get<T> (key);

        if (localStoreObj != null)
            await this.Insert (key, localStoreObj);
        return localStoreObj;
    }
    catch(Exception ex) {
        return await Task.FromResult<T> (null);
    }
}

public virtual async Task<T> Get<T>(string key) where T : class
{
    try
    {
        return await encryptedCache.GetObject<T> (key);
    }
    catch(KeyNotFoundException ex) {
        return await Task.FromResult<T> (null);
    }
    catch(Exception ex) {
        return await Task.FromResult<T> (null);
    }
}


public async Task Insert<T>(string key, T value, DateTimeOffset? expiration = default(DateTimeOffset?)) where T : class
{
    try
    {
        await memoryCache.InsertObject<T> (key, value, expiration);
    }
    catch {
    }
}
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