Ninna evaro React.JS meeda tutorial adigaru ga.... idi follow aipo

[Afdbuser123]

Naaku front-end knowledge close to nil. Basic html, css and javascript vachu. Maa team lo oka legacy app built on JSF undi. Danni nenu newer technology ki migrate/rewrite cheddamani plan chestunna. React vs Angular which is better ? Learning curve ela untundi for both ?.

[sri_india]

On 1/26/2020 at 7:48 PM, dasara_bullodu said:

@JANASENA telsindi chepta

 

1. Components can be declared as both Functional and class components ...
 

functional components ante they are declared as methods 

JS class components ante declare component as typescript class..  eg. “classname extends react.component“ (import react)

 

2. every react class component has props and state

props ante they are passed as html attributes to classes ..

for eg. <MyClass abcd=“dummy”/> ..

deeniki MyClass constructor(props) ani icchi.. props.abcd ni access cheskovacchu

 

state ante oka json object.. constructor lo key values initialize chestav. 
 

everytime state value change aithe component reload chestundi...

for eg.. this.state={“key”:”value”} ani constuctor lo icchi... tarvatha onclick method lo this.setState(“key”:“newvalue”) ani iste ...state maari component refresh autundi

so react lo just aa component refesh cheytaniki state ni refesh cheste saripotundi... this is the most important feature in react

 

3. Form/Map antha idea ledu bhayya.. Basically nenu bootstrap forms cheskoni state refresh chestunna

 

Nuvvu react expert laaa unnav kadha bro..gp

[sri_india]

On 1/26/2020 at 8:05 PM, dasari4kntr said:

can i explain as per my knowledge...but i am changing the order for better explanation...

 

2. What are props and state. 

for example , if you add two numbers in C language.
 

void add(int:a, int:b) {

c=a+b;

printf(c);

}

from the above code...
 

with one minor difference

props are immutable...

and state is mutable...thats why in react we write this as
 

this.setstate({

c:a+b

})

 

1. class component vs functional component

this guy has better explanation. please follow this article. basically functional components are simple to write so your final bundle size will be less and your code will be clean.

https://overreacted.io/how-are-function-components-different-from-classes/

steeled from this URL..

 

3. Forms and Maps in React. 

Forms(<input type="form" />)...i dont think you are going to use this in react. Because in react you dont follow traditional web application style where you post data to another page.

in react you are just using components. which are two types. controlled and uncontrolled.

for sending data to webservices you use fetch or axios..etc that too with in that component or event. (or some other place if your using redux)

MAP is not react related. is ES6 (javascript) function.

for example..

const temp =[1,2,3,4,5,6,7,8,9];

const result = temp.map(x=>{ return x%2===0});

console.log(result);

it do for-each in the array and creates new array for result.

 

 

Nuvvu react team lo work cheyachu bro.. super explanation

[visheshpaliwal]

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