在LINQ-to-SQL中将URI映射到字符串字段 [英] Mapping a URI to String-field in LINQ-to-SQL

问题描述

我正在尝试使用LINQ将URI作为字符串存储在数据库中.

I'm trying to store a URI as a string in a database, using LINQ.

[Column(Name = "Url", DbType = "nvarchar(255)")]
public Uri Url
{
    get
    {
        return new Uri(_url);
    }
    set
    {
        _url = value.AbsoluteUri;
    }
}

private string _url;

但是，当尝试使用以下代码获取数据时，这很好地映射到了我的数据库设计:

This maps nicely to my database design, however, when trying to fetch data using this code:

int id = 3;
_serie = new DataContext(connString).GetTable<Serie>();
var serie = _serie.FirstOrDefault(s => s.Id == id);

在最后一行，我得到一个异常

At the last line, I get an exception

System.InvalidCastException: Invalid cast from System.String to System.Uri etc

我需要怎么做才能正确处理代码中的URI，但是将其存储为数据库中的nvarchar(255)?看起来很简单，但我不知道自己在哪里做错了.

What do I need to do get correctly handle a URI in my code, but store it is a nvarchar(255) in my database? It seems simple, but I can't figure out where I'm doing it wrong.

推荐答案

和往常一样，写下问题可以帮助我意识到问题所在.以下代码解决了我的问题:

As always, writing down the question helped me realize the problem. The following code fixed my problem:

public Uri Url
{
    get
    {
        return new Uri(_url);
    }
    set
    {
        _url = value.AbsoluteUri;
    }
}

[Column(Name = "Url", DbType = "nvarchar(255)")]
private string _url;

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