我有一个包含一个nvarchar列这样一个数据库表：

I have a database table that contains an nvarchar column like this:

1|12.6|18|19

我有一个业务对象，有一个十进制数[]属性。

I have a Business Object that has a Decimal[] property.

我的LINQ查询看起来是这样的：

My LINQ Query looks like this:

var temp = from r in db.SomeTable select new BusinessObject {
    // Other BusinessObject Properties snipped as they are straight 1:1
    MeterValues = r.MeterValues.Split('|').Select(Decimal.Parse).ToArray()
};
var result = temp.ToArray();

这将引发NotSupportedException异常：法'System.String []斯普利特（字符[]）没有支持转换为SQL

This throws an NotSupportedException: Method 'System.String[] Split(Char[])' has no supported translation to SQL.

这有点儿吮吸:)有没有什么办法可以做到这一点，而不必一个字符串属性添加到业务对象或选择匿名类型，然后通过它迭代？

That kinda sucks :) Is there any way I can do this without having to add a string property to the business object or selecting an anonymous type and then iterating through it?

我目前的解决方案是：

var temp = from r in db.SomeTable select new {
    mv = r.MeterValues,
    bo = new BusinessObject { // all the other fields }
};
var result = new List<BusinessObject>();
foreach(var t in temp) {
    var bo = t.bo;
    bo.MeterValues = t.mv.Split('|').Select(Decimal.Parse).ToArray();
    result.Add(bo);
}
return result.ToArray(); // The Method returns BusinessObject[]

这是有点难看，虽然，与该临时表。

That's kinda ugly though, with that temporary list.

我试着加入让MV = r.MeterValues​​.Split（|），选择（Decimal.Parse）.ToArray（）但是，基本上导致到相同NotSupportedException异常

I've tried adding a let mv = r.MeterValues.Split('|').Select(Decimal.Parse).ToArray() but that essentially leads to the same NotSupportedException.

这是.NET 3.5SP1如果该事项。

This is .net 3.5SP1 if that matters.

推荐答案

您需要强制选择子句通过调用客户端上运行 .AsEnumerable（）第一：

You need to force the select clause to run on the client by calling .AsEnumerable() first:

var result = db.SomeTable.AsEnumerable().Select(r => new BusinessObject {
    ...
    MeterValues = r.MeterValues.Split('|').Select(Decimal.Parse).ToArray()
}).ToList();