Javascript 全部替换在 macOS/iOS 上的 safari 中不起作用

Question

I got below error in safari on macOS/iOS

Consider I need to replace a placeholder with actual price

const formattedPrice = '$1,100.00';
str.replace( /\|\|TOTAL_REPAYMENT_CHARGES\|\|/g, formattedPrice);

the result of above would be ,100.00

but if i use below one, it works

const formattedPrice = '$1,100.00';
str.replace( '||TOTAL_REPAYMENT_CHARGES||', formattedPrice)

the result would be $1,100.00

can someone explain what happened? thanks

Answer 1

When the first parameter of .replace is a regular expression, and the second parameter of .replace is a string, JS will parse the second parameter according to some rules , allowing for the concise replacement with the full match or a capture group. For example, $& indicates to replace with the full match:

 console.log('foo'.replace(/o/g, 'a$&'));

Above, each match is replaced with a , followed by the full match, and both full matches are o , so both matches are replaced with ao .

In your code, the $1 is being interpreted as "replace this part with the first capture group". But your code doesn't have any capture groups, so instead of matches being replaced with '$1,100.00' , they get replaced with ',100.00' .

To indicate a literal $ , use two $ s, like this:

const formattedPrice = '$$1,100.00';
//                       ^
str.replace( /\|\|TOTAL_REPAYMENT_CHARGES\|\|/g, formattedPrice);