How to use the LIKE operator in a C# Command?

问题

I need to insert a string into an Sql Command

search.CommandText = "SELECT * FROM Contacts WHERE Name like ' + @person + % + '";

What it the right way of using LIKE in a command?

回答1:

Should be:

SELECT * FROM Contacts WHERE Name like @person + '%'

@person is a parameter - you don't need single quotes around it. You only need to concatenate it with %, which should have quotes.

Keep in mind:

You could have kept it "SELECT * FROM Contacts WHERE Name like @person", and have the parameter value contain % (concatenate in C# is simpler to understand).
You may also want to escape other wildcard characters already in the string: %, _, [ and ].

回答2:

Use Syntax:

SELECT column_name(s)
FROM table_name
WHERE column_name LIKE pattern

The "%" sign can be used to define wildcards (missing letters in the pattern) both before and after the pattern.

For Example:

LIKE '%xy' would get you anything ending with 'xy'
LIKE '%xy%' would get you anything contains the 'xy'
LIKE 'xy%' would get you anything starting with 'xy'

回答3:

Is this what you mean?

searchPerson.CommandText = "SELECT * FROM Contacts WHERE Name LIKE '"+person+"%'";

回答4:

searchPerson.CommandText =  
   "SELECT * FROM Contacts WHERE Name like @person + '%'"

回答5:

searchPerson.CommmandText = "SELECT * FROM Contacts WHERE Name like '" + @person + "%'";

回答6:

select * from Contacts WHERE Name like '%' + '"+@person+"' + '%' 
select * from Contacts WHERE Name like '%' + '"+@person+"' 
select * from Contacts WHERE Name like '"+@person+"' + '%'

回答7:

This should work

"Select *  from customer where FirstName LIKE '"+TextBox1.Text + '%'+ "'   ";

回答8:

if Field type is Nvarchar use this code:

   "select * from Contacts where name like N'%"+person+"%'"

回答9:

"SELECT * FROM table_name like concat(@persons,'%')"

I used it.

来源：https://stackoverflow.com/questions/12399661/how-to-use-the-like-operator-in-a-c-sharp-command

标签

sql

sql-like