Take decimal integer part function in JS and take fractional part

1. Discard the fractional part, preserving the integer part

parseint (23.56);

Results: 23

2. Rounding up, with decimals on the integer part plus 1

Math.ceil (23.56)

Results: 24

3, rounded.

Math.Round (23.56)

Results: 24

4, rounding down

Math.floor (23.56)

Results: 23

Attached: How to determine the type of numeric input (without quotation marks when used!) ）

"^\\d+$"//nonnegative integer (positive integer    +   0)      
   ^[0-9]* [1-9] [0-9]*$ "//positive integer      
  " ^ ((-\\d+) | ( 0+) $ "//non-positive integer (negative integer    +   0)      
   ^-[0-9]*[1-9][0-9]*$ "//negative integer      
  " ^-?\\d+$ "//integer      
    "^\\d+ (\\.\\d+) $"//non-negative floating-point number (positive floating point    +   0)      
   " ^ ([0-9]+\\. [0-9]*[1-9][0-9]*) | ([0-9]*[1-9][0-9]*\\. [0-9]+) | ([0-9]*[1-9][0-9]*)) $ "//positive floating-point      
  " ^ (-\\d+ (\\.\\d+)?) | (0+ (\\.0+)?)) $ "//non-positive floating point number (negative floating point    +   0)      
  " ^ (-([0-9]+\\.[ 0-9]*[1-9][0-9]*) | ([0-9]*[1-9][0-9]*\\. [0-9]+) | ([0-9]*[1-9][0-9]*))) $ "//negative floating-point number      
  " ^ (-?\\d+) (\\.\\d+)? $ "//floating-point number

Example:

var   r   =   /^[0-9]*[1-9][0-9]*$///positive integer    //str for the character you want to judge Var str= "23.56"; r.test (str);    Executes the returned result true or False

Result: false

5, numerical rounding and taking of decimal parts

var a = "23.56"; var b = A.split ("."); var x=b[0];var y=b[1];

Results: x=23,y=56

Take decimal integer part function in JS and take fractional part