使用Linq和Lambda表达式从表中选择多个字段 [英] Selecting Many Fields From a Table using Linq and Lambda Expressions

问题描述

我有一个DataContext(db)，可以访问我的SQL Express数据库中的表，我只想从中提取tblItem表中多个字段中的三个:

I have a DataContext (db) that can access the tables in my SQL Express database, from which I would like to extract only three of the multiple fields in the tblItem table:

// this does not work - what is the correct way to do it?  
var items = db.tblItems.Select(i => i.id && i.name && i.totalAmount);

目的是将它们吐到一个csv文件中(以逗号分隔). var是执行此操作的最佳方法吗?

The intention is to spit these out into a csv file (comma separated). Is a var the best way to do this?

推荐答案

为此，您将必须使用一个专有对象:

You will have to use an anomynous object for this:

var items = db.tblItems.Select(i => 
            new { 
                  ID = i.id, 
                  Name = i.name, 
                  TotalAmount = i.totalAmount
                });

您可以像遍历任何其他集合一样遍历items:

You can iterate over items like over any other collection:

foreach(var item in items)
{
  //do stuff
}

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