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如何在 linq c# 上的 sql 中使用 like

[英]how use like in sql on linq c#

this not work这行不通

string[] DATE_Group = { "2020", "2021" }; //changing values
var query = _context.c10
            .Where(u => DATE_Group.Any(s => u.ON_DATE.Contains(s)))
            .ToList()
            .Select(u => new
            {
                User_NumberID = u.User_NumberID.ToString(),
            }).ToList();

I use this u.ON_DATE.Contains("2020") and work but not list or array only one value我使用这个u.ON_DATE.Contains("2020")并且工作但不列出或仅列出一个值

in sql SELECT * from C10 where ON_DATE like '%2020%' or ON_DATE like '%2021%' and in ON_DATE column content like this 1-3-2023 1-1-2021 5-1-2020在 sql SELECT * from C10 where ON_DATE like '%2020%' or ON_DATE like '%2021%' and in ON_DATE column content like this 1-3-2023 1-1-2021 5-1-2020

this error when used enter image description here使用时出现此错误 在此处输入图像描述

将以下代码用于您的 linq where 语句。

var myVar=context.Students.where(x=>x.Name.Contains("John")).SingleOrDefault();

I think this is a better way to get the data:我认为这是获取数据的更好方法:

var from = new DateTime(2020,1,1);
var to   = new DateTime(2022,1,1);
var query = _context.c10
            .Where(u => u.ON_DATE > from && u.ON_DATE < to )
            ...

EF Core cannot use Any with local collections (with small excpetion), only Contains is supported. EF Core 不能将Any与本地集合一起使用(具有较小的 excpetion),仅支持Contains

I would suggest to use function FilterByItems .我建议使用功能FilterByItems And use in query:并在查询中使用:


string[] DATE_Group = { "2020", "2021" }; //changing values

var query = _context.c10
    .FilterByItems(DATE_Group, (u, s) => u.ON_DATE.Contains(s), true)
    .Select(u => new
    {
        User_NumberID = u.User_NumberID.ToString()
    })
    .ToList();

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