how to use sql parameters instead

Question

0.00/5 (No votes)

See more:

I have this approach of code but I want to use parameters instead to prevent sql injection .. how to do that ?

here's my code :

C#

if (cn.State == ConnectionState.Closed) cn.Open();
            cm.Connection = cn;
            if (comboBox3.Enabled == true)
            {
                string searchFor2 = comboBox1.Text;
                string searchFor3 = comboBox2.Text;
                string selectSql = "SELECT " + searchFor2 + ", " + searchFor3 + " FROM itmsparts";
                SqlCommand com = new SqlCommand(selectSql, cn);
                try
                {
                    using (SqlDataReader read1 = com.ExecuteReader())
                    {
                        while (read1.Read())
                        {
                            ListViewItem parent = listView1.Items.Add(read1[0].ToString());
                            parent.SubItems.Add(read1[1].ToString());
                        }
                    }
                }
                finally
                {

                }
            }

Posted 10-Nov-15 9:10am

Ahmed Zoeil

Add a Solution

1 solution

Add a Solution

Add your solution here

Treat my content as plain text, not as HTML

Preview 0

…

Existing Members

Sign in to your account

...or Join us

Download, Vote, Comment, Publish.

Your Email
Password
Forgot your password?

Your Email
This email is in use. Do you need your password?
Optional Password

I have read and agree to the Terms of Service and Privacy Policy
Please subscribe me to the CodeProject newsletters

When answering a question please:

Read the question carefully.
Understand that English isn't everyone's first language so be lenient of bad spelling and grammar.
If a question is poorly phrased then either ask for clarification, ignore it, or edit the question and fix the problem. Insults are not welcome.
Don't tell someone to read the manual. Chances are they have and don't get it. Provide an answer or move on to the next question.

Let's work to help developers, not make them feel stupid.

This content, along with any associated source code and files, is licensed under The Code Project Open License (CPOL)

Sergey Alexandrovich Kryukov · Answer 1 · 2015-11-10T10:13:00

Using parametrized query is quite a right idea, and the code shown is not. Please see: http://msdn.microsoft.com/en-us/library/ff648339.aspx[^].

See also my past answers:
EROR IN UPATE in com.ExecuteNonQuery();[^],
hi name is not displaying in name?[^].

The query composed by concatenation with strings taken from UI. Not only repeated string concatenation is inefficient (because strings are immutable; do I have to explain why it makes repeated concatenation bad?), but yes, way more important issue is that it opens the doors to SQL injection. The user can write anything in the UI, including some SQL fragment. Are you getting the idea? This is how: http://xkcd.com/327.

—SA