using eval js code example
Example 1: Calculate string value in javascript, not using eval
let str = "12/5*9+9.4*2"
let res1 = eval(str)
console.log('res1:', res1)
let res2 = (new Function('return '+str)())
console.log('res2:', res2)
Example 2: eval in javascript
eval() -> is able to evalute the things inside it , like eval(a+b+c) , wher a=3,b=4,c=4 , so eval(a+b+c) = 11