C# Create multiple database programmatically

I followed a tutorial from Mahesh.
I created a windows application with a textbox and a button.
Textbox is used to enter the database name and click on the button to create the database.

The downside of it is that i can only create one database.

I normal code is from sql server the mdf file and the log file I had to enter it hard-coded but like to know how i can use textboxes to make those changes in order to create more than one database.

CreateDatabase = "CREATE DATABASE " + txtDatabase.Text +  " ON PRIMARY " +
                "(NAME = myDatabaseData," +
                " FILENAME = 'C:\\Database\\txtDatabase.Text.mdf', " +
                "SIZE = 3MB, MAXSIZE = 10MB, FILEGROWTH = 10%) " +
                "LOG ON (NAME = txtDatabase_log, " +
                "FILENAME = 'C:\\Database\\txtDatabase.Text.ldf', " +
                "SIZE = 1MB, " +
                "MAXSIZE = 5MB, " +
                "FILEGROWTH = 10%)";

On the form i want to add another textbox for the FILENAME what i have illustrated is not working and not sure how to make it work.
CreateDatabase = "CREATE DATABASE " + txtDatabase.Text +  " ON PRIMARY " +
                "(NAME = myDatabaseData," +
                " FILENAME = 'C:\\Database\\myDatabase.mdf', " +
                "SIZE = 3MB, MAXSIZE = 10MB, FILEGROWTH = 10%) " +
                "LOG ON (NAME = txtDatabase_log, " +
                "FILENAME = 'C:\\Database\\myDatabase.ldf', " +
                "SIZE = 1MB, " +
                "MAXSIZE = 5MB, " +
                "FILEGROWTH = 10%)";

By changing it as illustrated it works but only creates one database.
I want to create more than one database.
the user will be able to enter all the information in the textbox and click on the button to execute the code.
I appreciate for your assistance. Thanks in advance.