How to search in an array with npgsql? - npgsql

Question

I have an array column i would like to search.
The search term is like :
WHERE ARRAY['tag1','tag2'] <# tags
If i search like this (where donnee is the string of the text to search):
string variable1 = string.Empty;
string[] tags = donnee.Split(',');
if (tags.Length > 1)
{
foreach (string item in tags)
{
variable1 = variable1 + "'" + item + "',";
}
variable1 = variable1.Remove(variable1.Length - 1);
}
else
{
variable1 = variable1 + "'" + tags[0] + "'";
}
NpgsqlCommand cmd = new NpgsqlCommand("SELECT id,name FROM wincorrespondants WHERE (name ILIKE #donnee) OR (ARRAY[#var] <# tags) LIMIT 100", conn);
cmd.Parameters.AddWithValue("donnee", "%" + donnee + "%");
cmd.Parameters.AddWithValue("var", variable1);
the search don't work on the tag array but the program does not crash if there is a ' in the search string
If i search like this:
string variable1 = string.Empty;
string[] tags = donnee.Split(',');
if (tags.Length > 1)
{
foreach (string item in tags)
{
variable1 = variable1 + "'" + item + "',";
}
variable1 = variable1.Remove(variable1.Length - 1);
}
else
{
variable1 = variable1 + "'" + tags[0] + "'";
}
NpgsqlCommand cmd = new NpgsqlCommand("SELECT id,name FROM wincorrespondants WHERE (name ILIKE #donnee) OR (ARRAY["+variable1+"] <# tags) LIMIT 100", conn);
cmd.Parameters.AddWithValue("donnee", "%" + donnee + "%");
the program crash if there is a ' in the search string but work in other case (the program find the name the user is looking for or the user with the tags)
How do i format my search ?

Answer 1

Rather than trying to pass elements of the array, you should be sending the array itself as a parameter from Npgsql. For example:
var cmd = new NpgsqlCommand("SELECT id,name FROM wincorrespondants WHERE (name ILIKE #donnee) OR (#arr <# tags) LIMIT 100", conn);
cmd.Parameters.AddWithValue("arr", new[] {"tag1", "tag2" });