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TIPS & TRICKS OF JAVASCRIPT & REACT
const value_1 = "1"
const value_2 = "2"
function add(field_1, field_2){
return field_1 + field_2;
}
add(+value_1, +value_2);
const floatToInt = 23.9 | 0;
Note[if data is is static then you should use it. and don’t use any kind secret or confidential data here..]
const user = {
first_name: "Rowan",
last_name: "Atkinson"
}
window.user=user
const DemoComponent = ()=>{
const [show, setShow] = useState(false)
return (<div>
{show? <Message/>: ''}
</div>)
}
const DemoComponent = ()=>{
const [show, setShow] = useState(false)
return (<div>
{show && <Message/>}
</div>)
}
if (variable1 !== null || variable1 !== undefined || variable1 !== '') {
let variable2 = variable1;
}
const variable2 = variable1 || 'new';
Math.floor(4.9) === 4 // true
~~4.9 === 4 // true
switch (something) {
case 1:
doSomething();
break;
case 2:
doSomethingElse();
break;
case 3:
doSomethingElseAndOver();
break;
// And so on...
}
const cases = {
1: doSomething(),
2: doSomethingElse(),
3: doSomethingElseAndOver()
};
[Note: This one has performance issue I prefer use this one when you have crying need. Switch statement is more faster than this solution
if(x == 1 || x == 5 || x == 7) {
console.log('X has some value');
}
([1,5,7].indexOf(x) !=- 1) && console.log('X has some value!');
const param1 =1;
const param2 = 2;
const param3 = 3;
const param4 = 4;
function MyFunc =(param1, param2, param3, param4)=>{
console.log(param1, param2, param3, param4)
}
MyFunc(param1, param2, param3, param4)
const params = {param1: 1, param2: 2, param3: 3, param4: 4}
function MyFunc =({param1, param2, param3, param4})=>{
console.log(param1, param2, param3, param4)
}
MyFunc(params)
function Myfunc(value){
if(value){
console.log("you have a value")
}else{
throw new Error("You don't have a value")
}
}
NOTE: If you check error first then it’s don’t go else block but if you do first one it will check first value is exist then if not found it will go the else block.
function Myfunc(value){
return !value ? throw new Error("You don't have a value") : console.log("you have a value")
}
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