//START NEW ORDER BUTTON - IF USER CLICKS FIRST TIME NEW FORM APPEAR ELSE PAGE IN THE BACKGROUND WILL APPEAR
private void btnNew_Click(object sender, EventArgs e)
{
if (nextForm == null) //WILL CHECK IF USER CLICK FIRST TIME ON THE NEXT BUTTON
{
frmSelectForm sf = new frmSelectForm(); //IF YES, WILL CREATE OBJECT OF SELECT FORM TO SELECT NEW RECORD
sf.previousForm = this; //SET PREVIOUS FORM OF SELECT FORM = START UP FORM
sf.Show(); // SHOW SELECT FORM TO SELECT NEW RECORD
this.nextForm = sf; //SET NEXT FORM OF START UP FORM = SELECT FORM
}
else
{
this.nextForm.Show(); //IF SELECT FORM ALREADY OPEN IN BACKGROUND - WILL LOAD SELECT FORM TO SELECT NEW RECORD
}
this.Hide(); //HIDE START UP FORM WHEN LOAD SELECT FORM
}
//OPEN SAVED ORDER
private void btnOpen_Click(object sender, EventArgs e)
{
if (nextForm == null) //WILL CHECK IF USER CLICK FIRST TIME ON THE NEXT BUTTON
{
frmProductInfo fpi = new frmProductInfo(); //IF YES, WILL CREATE OBJECT OF PRODUCT INFORMATION FORM TO DISPLAY DATA FROM SAVED FILE
frmSelectForm fsl = new frmSelectForm(); // WILL CREATE OBJECT OF SELECT FORM, IF USER CLICK BACK BUTTON OF PRODUCT INFO FORM, AND IF SELECT FORM IS NOT LOADED, WILL OPEN FIRST TIME
fsl.Show(); //LOAD SELECT FORM
fsl.Hide(); //HIND SELECT FORM
fpi.ProdPrevForm = fsl; //SET PREVIOUS FORM OF PRODUCT INFO FORM = SELECT FORM
fsl.previousForm = this; //SET PREVIOUS FORM OF SELECT FORM = START UP FORM
fsl.nextForm = fpi; // SET NEXT FORM OF SELECT FORM = PRODUCT INFORMATION FORM
fpi.OpenSave(); //FUNCTION CALL FROM PRODUCT INFORMATION FORM TO DISPLAY PRODUCT INFORMATION OF SAVED FILE
fpi.Show(); // PRODUCT INFORMATION FORM WILL SHOW PRODUCT INFORMATION OF SAVED FILE
}
else //IF FORMS ARE ALREADY OPEN IN MEMORY
{
try
{
frmSelectForm fslnew = this.nextForm as frmSelectForm; // WILL OPEN SELECT FORM AS NEXT FORM WHICH IS ALREADY IN MEMORY
if (fslnew.nextForm == null) //BUT IF SELECT FORM IS NOT IN MEMORY - MEANS USER DID NOT TRY TO BACK AND FORTH
{
frmProductInfo fpinew2 = new frmProductInfo(); //
fpinew2.ProdPrevForm = fslnew; // SET PREVIOUS FORM OF PRODUCT INFO FORM = SELECT FORM
fslnew.nextForm = fpinew2; // SET NEXT FORM OF SELECT FORM = PRODUCT INFORMATION FORM
fpinew2.OpenSave(); //FUNCTION CALL FROM PRODUCT INFORMATION FORM TO DISPLAY PRODUCT INFORMATION OF SAVED FILE
fpinew2.Show(); //PRODUCT INFORMATION FORM WILL SHOW PRODUCT INFORMATION OF SAVED FILE
}
else
{
frmProductInfo fpinew = fslnew.nextForm as frmProductInfo; // WILL OPEN PRODUCT INFORMATION FORM AS NEXT FORM WHICH IS ALREADY IN MEMORY
fpinew.OpenSave(); //FUNCTION CALL FROM PRODUCT INFORMATION FORM TO DISPLAY PRODUCT INFORMATION OF SAVED FILE
fpinew.Show(); //PRODUCT INFORMATION FORM WILL SHOW PRODUCT INFORMATION OF SAVED FILE
}
}
catch (Exception ex)
{
Console.WriteLine(ex); //GIVES ERROR IF PROBLEM ARISE
}
}
this.Hide(); // HIDE START UP FORM
}