TIL 2020.11.13

Eventhandlers

onsubmit

• fires when the user submits a form

onmouseover

• fires when the user moves the mouse over a particular element

event.preventDefault()

• if the event does not get explicitly handled, its default action should not be taken as it normally would be

 

<textarea></textarea>

 

• can assign how many rows and width

<textarea rows="5" cols="40" id="comment_input"></textarea>

• allows user not to change size of textarea

textarea{

resize: none;

}

Local Storage

• get items: brings string out from local storage
• set items: save string inside local storage

reference: https://www.taniarascia.com/how-to-use-local-storage-with-javascript/

 

DOM

• html을 object관점에서 보는 방법
• DOM !== html
• DOM !==JavaScript
• document.body.(property)

 

String.prototype.trim()

• removes whitespace from both ends of a string

 

arrayLike

• An array-like or iterable object to convert to an array
• can get index key and length but cannot use array property like forEach method
• ex. string, object

 

Spread Syntax

• to combine into array when the type is not an array
• has to be iterable like array or arrayLike

 

QuerySelectorAll

• cannot put eventlistener together
• has to be per tag

 

tag.textContent or input.value

• remembers when event happens and where to call that values
• if you call in wrong spot, it will not show