In javascript

Question

I can detect a character in a string and then write a letter before that character?

Answer 1

// did you know regular expressions?

string = 'Heo world';

string = string.replace(/(?<=e)(?=o)/,'ll');

console.log(string);

Answer 2

https://code.sololearn.com/WedMt7d26oPO/?ref=app

Answer 3

Ipang i have a text for example "heo word" i want to write "ll" between the letter "e" and "o"

for later eval with javascript
eval()

Answer 4

visph thanks

Answer 5

What character to detect?
And where you write the letter?

Might help clear things up if you can provide an example.

Answer 6

Ipang visph
I'm not going to use it specifically with text, it is for mathematical expressions and that every time in the string there is a word before it, "Math." then use "eval ()"

(Translate by google )

Answer 7

share your code to get more accurate answer ;)

Answer 8

It for a calculator
https://code.sololearn.com/W5DWR1dC8808/?ref=app

Answer 9

You mean you read a string, for example

"Math. 9 x 2 ÷ 2"

Then you want the string to become

"9 * 2 / 2"

In order to be processed by eval()

Answer 10

For example
Text: cosh(5) -> Math.cosh(5)

Eval()

Answer 11

why don't you stuck at 'Math.'+string?

Answer 12

visph
?
eval("Math."+string)
?

Answer 13

just as you already do ^^

Answer 14

visph
could you explain me better

Sorry I'll be back in 2 hours I'm busy

Answer 15

You can make a list of function names e.g. [ "cos", "sin", "pow" ]. Then do a find & replace operation on the string before passing the string to eval().

let names = [ "sin", "cos", "tan" ];
for( let name of names )
{
// if string contains <name>
// replace it with "Math." + <name>
}