Why are my symbols not being replaced?

Question

0.00/5 (No votes)

See more:

I have code that is taking in a DataTable, converting each DataRow into a string, and then removing certain symbols ("|", "~", etc). However, my code is not removing these correctly. Strangely enough however, when I remove the underscore "_" from my charToRemove array, it does remove the pipes correctly.

Image with Pipes (Does not have underscore in charToRemove array)[^]

Image with Pipes Not Removed (has underscore in charToRemove array)[^]

What I have tried:

public static List<string> CleanMainLogTable(string liteConString)
{
    string[] charToRemove = new string[] { "*", "~", "|" , "_" };
    string cleanedEntry = "";
    SQLiteConnection liteCon = new SQLiteConnection(liteConString);
    liteCon.Open();
    DataTable dtbl = new DataTable();

    string select = "SELECT LogMessage FROM MainLog_Table";

    SQLiteCommand cmd = new SQLiteCommand(select, liteCon);
    SQLiteDataAdapter sqliteDAP = new SQLiteDataAdapter(cmd);
    sqliteDAP.Fill(dtbl);

    List<string> table = dtbl.AsEnumerable().Select(r => r.Field<string>(0)).ToList();
    int i = 0;

    foreach (string entry in table)
    {
        foreach(string c in charToRemove)
        {
            cleanedEntry = entry.Replace(c, string.Empty);
        }
        Console.WriteLine(i + " " + cleanedEntry);
        i++;
    }
    return null;
}

Posted 21-Sep-20 5:50am

stevenlam505

Updated 21-Sep-20 6:19am

Add a Solution

3 solutions

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)

F-ES Sitecore · Accepted Answer · 2020-09-21T06:12:00

Step through your code in the debugger and you should see what is going on. In your outer foreach "entry" will be something in your datatable, let's say "∗test". Your inner foreach declares "cleanedEntry" to be "entry" with "*" removed so cleanedEntry becomes "test" but entry is still "∗test". The next loop will remove any "~" in "entry", but entry is still "*test" so cleanedEntry is now "∗test" and so on. What you want to do is all the removals on the same string variable

C#

foreach (string entry in table)
{
    // define cleanedEntry to be the original text
    cleanedEntry = entry;

    foreach (string c in charToRemove)
    {
        // remove the char from cleanedEntry
        cleanedEntry = cleanedEntry.Replace(c, string.Empty);
    }
    Console.WriteLine(i + " " + cleanedEntry);
    i++;
}

That probably gives you another problem though, your orignal "table" List will remain unchanged as when you enumerate through the values you get a copy of the value rather than a reference to the value so your removal is done on a copy of the string in the List, not the List itself so that stays unchanged. To update the actual List;

C#

List<string> table = dtbl.AsEnumerable().Select(r => r.Field<string>(0)).ToList();

for(int i = 0; i < table.Count; i++)
{
    foreach (string c in charToRemove)
    {
        table[i] = table[i].Replace(c, string.Empty);
    }
    Console.WriteLine(i + " " + table[i]);
}

Richard MacCutchan · Accepted Answer · 2020-09-21T06:12:00

C#

foreach (string entry in table)
{
    foreach(string c in charToRemove)
    {
        cleanedEntry = entry.Replace(c, string.Empty);
    }
    Console.WriteLine(i + " " + cleanedEntry);
    i++;
}

Each time you call replace, you use the original string as the source, and the cleanedEntry string as the destination. So the final result will be the original string with the underscores removed.

Try:

C#

foreach (string entry in table)
{
    cleanedEntry = entry;
    foreach(string c in charToRemove)
    {
        cleanedEntry = cleanedEntry.Replace(c, string.Empty);
    }
    Console.WriteLine(i + " " + cleanedEntry);
    i++;
}

OriginalGriff · Accepted Answer · 2020-09-21T06:19:00

Simple: your inner loop processes the same input string each time.
Change it to this:

C#

foreach (string entry in table)
    {
    cleanedEntry = entry;
    foreach (string c in charToRemove)
        {
        cleanedEntry = cleanedEntry.Replace(c, string.Empty);
        }
    Console.WriteLine(i + " " + cleanedEntry);
    i++;
    }

And it'll work.

Why are my symbols not being replaced?

3 solutions

Solution 1

Solution 2

Solution 3

Add your solution here

Preview 0