Warning: file_get_contents(/data/phpspider/zhask/data//catemap/2/csharp/268.json): failed to open stream: No such file or directory in /data/phpspider/zhask/libs/function.php on line 167

Warning: Invalid argument supplied for foreach() in /data/phpspider/zhask/libs/tag.function.php on line 1116

Notice: Undefined index: in /data/phpspider/zhask/libs/function.php on line 180

Warning: array_chunk() expects parameter 1 to be array, null given in /data/phpspider/zhask/libs/function.php on line 181

Warning: file_get_contents(/data/phpspider/zhask/data//catemap/7/sqlite/3.json): failed to open stream: No such file or directory in /data/phpspider/zhask/libs/function.php on line 167

Warning: Invalid argument supplied for foreach() in /data/phpspider/zhask/libs/tag.function.php on line 1116

Notice: Undefined index: in /data/phpspider/zhask/libs/function.php on line 180

Warning: array_chunk() expects parameter 1 to be array, null given in /data/phpspider/zhask/libs/function.php on line 181
C# sqlite查询后读卡器丢失值_C#_Sqlite_Uwp - Fatal编程技术网

C# sqlite查询后读卡器丢失值

C# sqlite查询后读卡器丢失值,c#,sqlite,uwp,C#,Sqlite,Uwp,所以我试图从一个现有的SQLite数据库中读入值,它最初似乎可以工作,但在查询之后,当我试图读入它们时,它似乎丢失了这些值 我做错了什么 publicobservableCollection GetAllAssets() { _DbConn.Open(); var命令=_DbConn.CreateCommand(); var allAssets=新的ObservableCollection(); command.CommandText= @" 选择* 来自资产 "; 使用(var reader

所以我试图从一个现有的SQLite数据库中读入值,它最初似乎可以工作,但在查询之后,当我试图读入它们时,它似乎丢失了这些值

我做错了什么

publicobservableCollection GetAllAssets()
{
_DbConn.Open();
var命令=_DbConn.CreateCommand();
var allAssets=新的ObservableCollection();
command.CommandText=
@"
选择*
来自资产
";
使用(var reader=command.ExecuteReader())
{
while(reader.HasRows)
{
资产=新资产();
asset.AssetId=reader.GetInt32(0);
asset.AssetTypeId=reader.GetInt32(1);
asset.Name=reader.GetString(2);
asset.FileLocation=reader.GetString(3);
asset.IsCustom=reader.GetBoolean(4);
asset.AssetSectionId=reader.GetInt32(5);
asset.ThumbFileLocation=reader.GetString(6);
所有资产增加(资产);
}
}
_DbConn.Close();
归还所有资产;
}
如果
reader
包含一行或多行,则该方法返回
true
,如果不包含一行或多行,则返回
false
,但不会将
reader
前进到下一行。

您必须使用以下方法:


多谢了,成功了!你应该在视频下面写一条评论,说明所教的东西不起作用。并发布此问题的链接;)
public ObservableCollection<Asset> GetAllAssets()
{
    _DbConn.Open();

    var command = _DbConn.CreateCommand();
    var allAssets = new ObservableCollection<Asset>();

    command.CommandText =
    @"
        SELECT * 
        FROM asset 
    ";

    using (var reader = command.ExecuteReader())
    {
        while (reader.HasRows)
        {
            Asset asset = new Asset();
            asset.AssetId = reader.GetInt32(0);
            asset.AssetTypeId = reader.GetInt32(1);
            asset.Name = reader.GetString(2);
            asset.FileLocation = reader.GetString(3);
            asset.IsCustom = reader.GetBoolean(4);
            asset.AssetSectionId = reader.GetInt32(5);
            asset.ThumbFileLocation = reader.GetString(6);

            allAssets.Add(asset);
        }
    }

    _DbConn.Close();

    return allAssets;
}
while (reader.Read())
......................