Question

string alpha="this is text";
string sql = "INSERT INTO dokimastikospinakas (pliroforia) VALUES ('alpha')";

Which is the right syntax to pass a c# variable into an sql command?

Answer 1

Here’s just one very simple method:

var yourTextValue = "this is text";
using (var db = new SqlConnection()) {
    db.Open();

    var command =
        new SqlCommand("INSERT INTO dokimastikospinakas (pliroforia) VALUES (@textValue);", db);
    command.Parameters.AddWithValue("@textValue", yourTextValue);

    command.ExecuteNonQuery();
}

EDIT: You’d actually need some connection string for SqlConnection constructor, of course. And modified variable names by popular demand.