code-201-reading-notes

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Domain modeling

Domain modeling is the process of creating a conceptual model in code for a specific problem.

Generat Random Numbers

in this case we use Math.random() function

the methods can be added to a prototype instead of the object itself

• When modeling a single entity that’ll have many instances, build self-contained objects with the same attributes and behaviors.
• Model its attributes with a constructor function that defines and initializes properties.
• Model its behaviors with small methods that focus on doing one job well.
• Create instances using the new keyword followed by a call to a constructor function.
• Store the newly created object in a variable so you can access its properties and methods from outside.
• Use the this variable within methods so you can access the object’s properties and methods from inside.

Tables

There are several types of information that need to be displayed in a grid or table. For example: sports results, stock reports, train timetables. A table represents information in a grid format.

Basic Table Structure

• The table element is used to create a table. The contents of the table are written out row by row.
• The table element is used to create a table. The contents of the table are written out row by row.
• Each cell of a table is represented using a td element. (The td stands for table data.) At the end of each cell you use a closing td tag.

Table headings

The th element is used just like the td element but its purpose is to represent the heading for either a column or a row. (The th stands for table heading.) Even if a cell has no content, you should still use a td or th element to representb the presence of an empty cell otherwise the table will not render correctly.

Spanning columns

Sometimes you may need the entries in a table to stretch across more than one column. The colspan attribute can be used on a th or td element and indicates how many columns that cell should run across.

Colspan=”n of columns that u want it to strech in”

Spanning Rows

You may also need entries in a table to stretch down across more than one row. The rowspan attribute can be used on a th or td element to indicate how many rows a cell should span down the table.

Rowspan=”n of rows that u want it to strech in”

Long tables

There are three elements that help distinguish between the main content of the table and the first and last rows

• The headings of the table should sit inside the thead element.
• The body should sit inside the tbody element.
• The footer belongs inside the tfoot element.