JavaScript conversion between numeric and string types_javascript skills

1. Conversion from numeric type to String type
Assume that the numeric type (int/float/double) variable is: num and the string obtained after conversion is: str
Then it is converted to There are three ways to use strings, as follows:
(1) str = String.valueOf(num);
(2) str =Integer.toString(num);
(3) str =num "";
2. Conversion from String type to numeric type (take int as an example here, double and float are similar)
There are two conversion methods, as follows:
( 1) num=Integer.parseInt(str);
(2) num=Integer.valueOf(str).intValue();
This part is relatively easy to implement, so no examples will be given here.