public static List <DDLClass> DataCollection; //if you take out static, everyone has their own version of the page. with static, one copy for everyone
protected void Page_Load(object sender, EventArgs e)
{
//this event will happen EACH AND EVERY time your page is executed
//this event will happen BEFORE ANY of YOUR control events happen
//this is a great place to initilize items(controls) that are common
//to many events and need to be done every time
//e.x.: old messages should be cleared out on every pass
// you can empty the MessageLabel control under EACH event
// OR you can do it ONCE here for ALL events
MessageLabel.Text = "";
//this is a great place to do 1st time initialization of controls
// (similar to the else side of the IsPost from Razor)
if (!Page.IsPostBack) //same thing as (Page.IsPostBack == false) or (Page.IsPostBack != true)
{
//load the DDL on the first pass.
//create an instance of a collection (List<T>; T == class DDLClass)
//create 4 record instances for the collection
//place the collection into the DDL
DataCollection = new List <DDLClass>();
DataCollection.Add(new DDLClass(1, "COMP1008"));
DataCollection.Add(new DDLClass(2, "CPSC1517"));
DataCollection.Add(new DDLClass(3, "DMIT1508"));
DataCollection.Add(new DDLClass(4, "DMIT2018"));
//sort the data collection for the ddl by program course name
//syntax: collectionname.Sort((x,y) => x.fieldname.CompareTo(y.fieldname))
//collectionname is where your data resides (List<t>)
//(x,y) represent any two values (records) in your collection at any point in time
//=> (lamda) can be thought of as "do the following to x and y" (delegate)
//our delegate for lamda is comparing x and y on the fieldname
// x CompareTo y is an ascending sort
// y CompareTo x is a descending sort
DataCollection.Sort((y, x) => x.DisplayField.CompareTo(y.DisplayField));
//steps in loading your DDL
//assume that the DataCollection is actually database data
// a) assign the data source to the control
CollectionChoiceList.DataSource = DataCollection; //collectionchoicelist is id of what was used for the dropdownlist in BasicControls.aspx
//<option value=somevalue> sometext </option>
//define what somevalue and sometext is in the data collection
// b) indicate the display field to the control
CollectionChoiceList.DataTextField = "DisplayField"; //Non-Object Style
// c) indicate the value field to the control
CollectionChoiceList.DataValueField = nameof(DDLClass.ValueField); //Object Style; preferable because you can use intellisense
// d) physically bind the data to the control
CollectionChoiceList.DataBind();
//optional prompt line??
CollectionChoiceList.Items.Insert(0, "select ..."); //Index for COMP1008 changes from 3 to 4?
}
}
protected void ResetFields()
{
NumberChoice.Text = "";
ChoiceList.ClearSelection();
//ChoiceList.SelectedIndex = -1; //index -1 will not be found, optionally way
CollectionChoiceList.ClearSelection();
ProgrammingCourseActive.Checked = false;
AlterLabel.ForeColor = System.Drawing.Color.Black;
}
protected void ResetFields()
{
DisplayDataRO.Text = "";
ProgrammingCourseActive.Checked = false;
ChoiceList.ClearSelection();
//ChoiceList.SelectedIndex = -1; //This is an optional way of deselecting
CollectionChoiceList.ClearSelection();
AlterLabel.ForeColor = System.Drawing.Color.Black;
}
protected void Page_Load(object sender, EventArgs e)
{
//this event will happen EACH and EVERY time your page is executed
//this event will happen BEFORE ANY of YOUR control events happen
//this is a great place to initialize items (controls) that are
// common to many events and need to be done every time
//example: old messages should be cleared out on every pass
// you can empty the MessageLabel control under each event
// OR do it once here all ALL events
MessageLabel.Text = "";
//this is a great place to do 1st time initialization of controls
//(similar to the else side of the IsPost from Razor)
if (!Page.IsPostBack) //(Page.IsPostBack == false)
{
//load the DDL on the 1st pass
//create an instance of a collection (List<T>) (T == class called DDLCLass)
//create 4 instance of DDLClass for the collection
//place the collection into the DDL
DataCollection = new List <DDLClass>();
DataCollection.Add(new DDLClass(2, "CPSC1517"));
DataCollection.Add(new DDLClass(1, "COMP1008"));
DataCollection.Add(new DDLClass(4, "DMIT2018"));
DataCollection.Add(new DDLClass(3, "DMIT1508"));
//sort the data collection for the ddl by program course name
//syntax collectionname.Sort((x,y) => x.fieldname.CompareTo(y.fieldname))
//collectionname is where your List<T> resides
//(x,y) represents any two values (records) in your collection at any point in time
//=> (lamda) can be thought of as "do the following to x an y" (delegate)
//our delegate for lamba is comparing x and y on the fieldname
// x CompareTo y is an ascending sort
// y CompareTo x is a descending sort
DataCollection.Sort((x, y) => x.DisplayField.CompareTo(y.DisplayField));
//steps in loading your DDL
//assume that the DataCollection is actually database data
//a) assign the data source to the control
CollectionChoiceList.DataSource = DataCollection; //just the data
//<option value=theValue> theDisplay </option>
//b) indicated the display field to the controller
CollectionChoiceList.DataTextField = "DisplayField"; //non object style
//c) inidcated the value field to the controller
CollectionChoiceList.DataValueField = nameof(DDLClass.ValueField); //object style
//d) physically bind the data to the control
CollectionChoiceList.DataBind();
//optional prompt line??
CollectionChoiceList.Items.Insert(0, "select ....");
}
}
protected void Page_Load(object sender, EventArgs e)
{
//this event will happen EACH and EVERY time your page is executed
//this event will happen BEFORE ANY of YOUR control events happen
//this is a great place to intialize items (controls) that are common
// to many events and need to be done every time
//example: old messages should be cleared out on every pass
// you can empty the MessageLabel control under each event
// OR do it once here for ALL events
MessageLabel.Text = "";
//this is a great place to do 1st time intialization of controls
//(similar to the else side of the IsPost from Razor)
if (!Page.IsPostBack) //Page.IsPostBack == false
{
//load the DDL on the first pass
//create a new instance of the DDLClass
//create 4 entries for the collection
//place the collection into the DDL
DataCollection = new List <DDLClass>();
DataCollection.Add(new DDLClass(1, "COMP1008"));
DataCollection.Add(new DDLClass(2, "CPSC1517"));
DataCollection.Add(new DDLClass(3, "DMIT1508"));
DataCollection.Add(new DDLClass(4, "DMIT2018"));
//SORT the data collection for the DDL by course name
//syntax: CollectionName.Sort((x,y) => x.fieldname.CompareTo(y.namefield))
//collection name is where your List<t> resides
//(x,y) represent and TWO values (records) in your collection at any point in time
// =>(lamda) can be thought of as "do the following to x and y"
// our delgate for => is comparing x and y on fieldname
//x compare to y is an ascending sort
//y compare to x is an descending sort
DataCollection.Sort((x, y) => x.DisplayField.CompareTo(y.DisplayField));
//steps in loading your DDL
//A) Assign the datasource to the control
CollectionChoiceList.DataSource = DataCollection;
//B) Indicate the display field to the control
//<option value=valuefield>DisplayField</option>
CollectionChoiceList.DataTextField = "DisplayField"; //nonobject style
//C) Indicate the value field to the control
CollectionChoiceList.DataValueField = nameof(DDLClass.ValueField); //object style
//D) Physically bind the data to the control
CollectionChoiceList.DataBind();
//Optional promptline
CollectionChoiceList.Items.Insert(0, "select...");
}
}
protected void Page_Load(object sender, EventArgs e)
{
//This event will happen EACH and EVERY time your page is executed
//this event will happen BEFORE ANY of YOUR control events happen
//this is a great place to initialise items(controls) that are common
// to many events. and need to be done everytime
//Example:
// old messages should be cleared our on every pass
// you can empty the MessageLabel control under each event
// OR DO it ONCE here for ALL events
MessageLabel.Text = "";
//this is a great place to do first time initialization of controls.
// (simlilar to the else side of the "IsPost" from Razor)
//-----
if (!Page.IsPostBack) //or if(Page.IsPostBack == false)or if(Page.IsPostBack != true)
{
//load the DDL on the 1st pass
//create an instane of a collection (List<T>); T = class DDLClass)
//create 4 record instances for the collection
//place the collection into the DDL
//normaly, the collection is the result of a qury to your database
}
DataCollection = new List <DDLClass>();
DataCollection.Add(new DDLClass(1, "COMP 1008"));
DataCollection.Add(new DDLClass(2, "CPSC-1517"));
DataCollection.Add(new DDLClass(3, "DMIT-1508"));
DataCollection.Add(new DDLClass(4, "DMIT-2018"));
//sort the data collection for the ddl by program course name
//Syntax: collectionname.Sort((x,y) => x.fieldname.Compare(y.fieldname))
//collectionname is where your data resides (List<T>).
//(x,y) represents any two values (records0 in your collection in any point in time
// = (lamda) can be though of as "do the following to x and y" (delegate)
//our delegate for lamda is compairing x and y on the fieldname
// x CompaireTo y is an ascending sort
// y CompairTo x is an descending sort
DataCollection.Sort((x, y) => x.DisplayField.CompareTo(y.DisplayField));
//steps in loading your DDL:
//assume the DataCollection is actually database data
//a) assign the data source to the controll.
CollectionChoiceList.DataSource = DataCollection; //just the data
//<option value ="somevalue"> some text </option>
//defince what somevalue and sometext is in the data collection
//b.) indicate the dicplay field to the control
CollectionChoiceList.DataTextField = nameof(DDLClass.DisplayField); //non-object style
//c.) indicate the value field to the control
CollectionChoiceList.DataValueField = nameof(DDLClass.ValueField); //this is perferable since that the program is
//ensured that the correct object is called
//d.)physically bind the data to the control
CollectionChoiceList.DataBind();
//optional prompt line??
CollectionChoiceList.Items.Insert(0, "select...");
}