private void txtBookID_PreviewKeyDown(object sender, PreviewKeyDownEventArgs e)
{
try
{
if (e.KeyData == Keys.Tab)
{
BooksDetail bd = ctx.BooksDetails.Where(x => x.BookID.ToString() == txtBookID.Text).First();
txtBookTitle.Text = bd.BookTitle;
}
}
catch (InvalidOperationException)
{
txtBookTitle.Text = "";
toolStripLabel1.Text = "Please enter a valid Book ID before pressing tab";
}
}
private void btnAdd_Click(object sender, EventArgs e)
{
BooksDetail b = new BooksDetail();
b.BookTitle = "";
b.Author = "";
b.BookType = "";
b.ISBN = null;
b.TotalStock = null;
b.NumberLoaned = null;
blst.Add(b);
ctx.BooksDetails.Add(b);
posn = blst.Count - 1;
PopulateTextBoxes();
txtBookID.Text = "";
}
private void btnDelete_Click(object sender, EventArgs e)
{
int curPos = posn;
BooksDetail b = blst[curPos];
try
{
ctx.BooksDetails.Remove(b);
ctx.SaveChanges();
if (posn > 0)
{
posn--;
PopulateTextBoxes();
}
}
catch (DbUpdateException db) //rows linked to loan tran details cannot be deleted due to relationship
{
MessageBox.Show("This books have previous loan records.", "Unable to delete record");
}
}
private void btnReturn_Click(object sender, EventArgs e)
{
Int32 selectedRowCount = dataGridView1.Rows.GetRowCount(DataGridViewElementStates.Selected);
if (selectedRowCount > 0)
{
foreach (DataGridViewRow row in dataGridView1.SelectedRows)
{
int bookID = Convert.ToInt32(row.Cells[1].Value);
BooksDetail bd = ctx.BooksDetails.Where(x => x.BookID == bookID).First();
bd.NumberLoaned = Convert.ToInt16(bd.NumberLoaned - 1);
int transactionID = Convert.ToInt32(row.Cells[0].Value);
LoanTransDetail loanTran = ctx.LoanTransDetails.Where(x => x.BookID == bookID && x.TransactionID == transactionID).First();
loanTran.LoanStatus = "In";
loanTran.DateActualReturn = DateTime.Now;
ctx.SaveChanges();
dataGridView1.Rows.RemoveAt(row.Index);
}
}
toolStripStatusLabel1.Text = "Successfully Updated.";
}
