/// <summary>
/// This method list all the records in Users.dat
/// </summary>
/// <param></param>
/// <returns>A list of all Authors in the file/returns>
public static List <AuthorProduct> ListAllRecords()
{
List <AuthorProduct> allAuthors = new List <AuthorProduct>();
if (File.Exists(filePath))
{
using (StreamReader sr = new StreamReader(filePath))
{
// read the first line in the file;
string line = sr.ReadLine();
while (line != null)
{
//split the line to get the Id
string[] fields = line.Split(',');
AuthorProduct anAuthor = new AuthorProduct();
anAuthor.AuthorId = Convert.ToInt32(fields[0]);
anAuthor.ProductId = Convert.ToInt32(fields[1]);
allAuthors.Add(anAuthor);
// read the next line
line = sr.ReadLine();
}
}
}
else
{
MessageBox.Show("File not found!", "Error", MessageBoxButtons.OK, MessageBoxIcon.Error);
}
return(allAuthors);
}
/// <summary>
/// This function updates the fields of an object AuthorProduct
/// </summary>
/// <param name="anAuthor"></param>
/// <returns>True if the update was succesfull; False otherwise</returns>
public static bool Update(AuthorProduct anAuthor)
{
if (File.Exists(filePath))
{
StreamReader sr = new StreamReader(filePath);
StreamWriter sw = new StreamWriter(filePath2, true);
// read the first line
string line = sr.ReadLine();
while (line != null)
{
string[] fields = line.Split(',');
if (anAuthor.AuthorId != Convert.ToInt32(fields[0]))
{
//write to the new file
sw.WriteLine(line);
}
else
{
// write the updated User to the new file
sw.WriteLine(anAuthor.AuthorId + "," + anAuthor.ProductId);
}
// Read the next line
line = sr.ReadLine();
}
//Close the files
sr.Close();
sw.Close();
//delete the old file
File.Delete(filePath);
//Rename the new file with the old name
File.Move(filePath2, filePath);
}
else
{
MessageBox.Show("File Not Found", "Error");
return(false);
}
return(true);
}
/// <summary>
/// This method search for the first occurence of an ID into the file.
/// </summary>
/// <param name="id"></param>
/// <returns>If found returns an object AuthorProduct, return and object AuthorProduct set to null if the ID is not found /returns>
public static List <AuthorProduct> SearchRecord(int id, int searchBy = 0)
{
int Idx = 0; //Default Search by Author ID
if (searchBy > 0)
{
Idx = 1;
} //If searchBy is different of author ID, force search by Book Id
List <AuthorProduct> authorBooks = new List <AuthorProduct>();
if (File.Exists(filePath)) // Check if the file exists beforre reading it.
{
using (StreamReader sr = new StreamReader(filePath))
{
// read the first line in the file;
string line = sr.ReadLine();
while (line != null)
{
//split the line to get the Id
string[] fields = line.Split(',');
if (id == Convert.ToInt32(fields[Idx]))
{
// Author or Book Id found
AuthorProduct anAuthor = new AuthorProduct();
anAuthor.AuthorId = Convert.ToInt32(fields[0]);
anAuthor.ProductId = Convert.ToInt32(fields[1]);
authorBooks.Add(anAuthor);
}
// read the next line
line = sr.ReadLine();
}
}
}
else
{
MessageBox.Show("File not found!", "Error", MessageBoxButtons.OK, MessageBoxIcon.Error);
}
return(authorBooks);
}
