public string InsertReadList(string authorName, string bookTitle, DateTime readingDate, int page, int rating)
{
if (string.IsNullOrEmpty(authorName))
{
return("Insert failed, because authorName should not be null or empty string.");
}
if (string.IsNullOrEmpty(bookTitle))
{
return("Insert failed, because bookTitle should not be null or empty string.");
}
if (page <= 0)
{
return("Insert failed, because book must have more pages than zero or less.");
}
if (rating <= 0 || rating > 5)
{
return("Insert failed, because rating must be more than one and less than five.");
}
using (ReadListContext db = new ReadListContext())
{
ReadList readList = new ReadList()
{
AuthorName = authorName,
BookTitle = bookTitle,
ReadingDate = readingDate,
Page = page,
Rating = rating
};
db.ReadLists.Add(readList);
db.SaveChanges();
return("Insert successful!");
}
}
public string UpdateReadList(ReadList newReadList)
{
using (ReadListContext db = new ReadListContext())
{
ReadList temp = db.ReadLists.Find(newReadList.Id);
if (temp == null)
{
return("Update failed, because row with this id does not exist.");
}
if (string.IsNullOrEmpty(newReadList.AuthorName))
{
return("Insert failed, because authorName should not be null or empty string.");
}
if (string.IsNullOrEmpty(newReadList.BookTitle))
{
return("Insert failed, because bookTitle should not be null or empty string.");
}
if (newReadList.Page <= 0)
{
return("Update failed, because book must have more pages than zero or less.");
}
if (newReadList.Rating <= 0 || newReadList.Rating > 5)
{
return("Update failed, because rating must be more than one and less than five.");
}
temp.AuthorName = newReadList.AuthorName;
temp.BookTitle = newReadList.BookTitle;
temp.Page = newReadList.Page;
temp.Rating = newReadList.Rating;
temp.ReadingDate = newReadList.ReadingDate;
db.Entry(temp).State = EntityState.Modified;
db.SaveChanges();
return("Update successful!");
}
}
public string DeleteById(int id)
{
using (ReadListContext db = new ReadListContext())
{
ReadList readList = db.ReadLists.Find(id);
if (readList != null)
{
db.Entry(readList).State = EntityState.Deleted;
db.SaveChanges();
return("Delete successful!");
}
else
{
return("Delete failed, Row with this id does not exist.");
}
}
}