如何在linq查询中使用like运算符

问题描述：

如何在linq中使用like运算符。我有下表。

i只想过滤并获得如下条件的记录

whereTemp contains（ S1，S2）==>我想过滤整列中的所有S1和S2。

我也想要在哪里Temp不在里面（％Fi％，％K％）记录。

我们如何写LINQ查询。

下面的样本表。

Hi,

How to use like operator in linq. i have the below table.

i just want to filter and get the records like below condition

"where "Temp contains" ("S1,S2") ==> i want to filter all S1 and S2 in entire columns.

also i want to eleminate "where Temp not in like (%Fi%,%K%) records.

How do we write in LINQ Query.

sample table below.

Emp	Temp
100	S1+S2+S3
100	S1+S2+S3
100	S1+S2+S3
100	S1+S2+S3
100	S1+S2+S3
100	Z1+Z2+Z3
100	Z1+Z2+Z3
100	Z1+Z2+Z3
100	Z1+Z2+Z3
100	Z1+Z2+Z3
100	Z1+Z2+Z3
100	Z1+Z2+Z3
100	Z1+Z2+Z3
100	Z1+Z2+Z3
100	S1+Z3
100	L1+L2
100	L1+L2
100	A+B
100	C+DD
100	EE+Fin
100	Ke+W

我尝试过：

What I have tried:

Values = "A1,A2"
Var query1 = (from a in tbl1.AsEnumerable()

                     where r.Field<string>("TEMP").Contains(Values)

答

假设 tbl1 是一个数据表对象，你必须结合使用其中 + 任何方法。

所以，拿查看示例并根据需要更改查询。

Assuming that tbl1 is a datatable object, you have to combine Where + Any method.

So, take a look at example and change your query to your needs.

DataTable dt = new DataTable();
dt.Columns.Add(new DataColumn("Emp", typeof(int)));
dt.Columns.Add(new DataColumn("Temp", typeof(string)));
dt.Rows.Add(new object[]{100, "S1+S2+S3"});
dt.Rows.Add(new object[]{100, "S1+S2+S3"});
dt.Rows.Add(new object[]{100, "S1+S2+S3"});
dt.Rows.Add(new object[]{100, "S1+S2+S3"});
dt.Rows.Add(new object[]{100, "S1+S2+S3"});
dt.Rows.Add(new object[]{100, "Z1+Z2+Z3"});
dt.Rows.Add(new object[]{100, "Z1+Z2+Z3"});
dt.Rows.Add(new object[]{100, "Z1+Z2+Z3"});
dt.Rows.Add(new object[]{100, "Z1+Z2+Z3"});
dt.Rows.Add(new object[]{100, "Z1+Z2+Z3"});
dt.Rows.Add(new object[]{100, "Z1+Z2+Z3"});
dt.Rows.Add(new object[]{100, "Z1+Z2+Z3"});
dt.Rows.Add(new object[]{100, "Z1+Z2+Z3"});
dt.Rows.Add(new object[]{100, "Z1+Z2+Z3"});
dt.Rows.Add(new object[]{100, "S1+Z3"});
dt.Rows.Add(new object[]{100, "L1+L2"});
dt.Rows.Add(new object[]{100, "L1+L2"});
dt.Rows.Add(new object[]{100, "A+B"});
dt.Rows.Add(new object[]{100, "C+DD"});
dt.Rows.Add(new object[]{100, "EE+Fin"});
dt.Rows.Add(new object[]{100, "Ke+W"});

string[] values = new string[]{"S1", "S2"};
var qry = dt.AsEnumerable()
	.Where(x=> x.Field<string>("Temp")
			.Split(new string[]{"+"}, StringSplitOptions.RemoveEmptyEntries)
			.Any(y=>values.Contains(y)));

结果：

Result:

Emp Temp
100 S1+S2+S3 
100 S1+S2+S3 
100 S1+S2+S3 
100 S1+S2+S3 
100 S1+S2+S3 
100 S1+Z3

string[] values = new string[] { "S1", "S2" };
string[] notval = new string[] { "Fi", "K" } ;
var qry = tbl1.AsEnumerable()
                .Where(x => (x.Field<string>("Temp").Contains(values[0]) || 
                            x.Field<string ("Temp").Contains(values[1]) &&
                           (!x.Field<string>("Temp").Contains(notval[0]) || 
                            !x.Field<string ("Temp").Contains(notval[1])));
int count = qry.Count;

您可以使用 Aggregate 来满足多目标值。例如。

You can use Aggregate to cater for multipile target values. Something like.

var query = dt.AsEnumerable();
           var strs = new[] { "S1", "S2" };
           query = strs.Aggregate(query, (current, s) => current.Where(x => x.Field<string>("Temp").Contains(s)));

如何在linq查询中使用like运算符

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