千分位 区分 正则

function numFormat( num) {

var res = num. toString(). replace( / \d + /, function ( n) { // 先提取整数部分

return n. replace( /( \d )(?=( \d {3} ) +$ )/ g, function ( $1) {

return $1 + ",";

});

})

return res;

}

var a = 1234567894532;

var b = 673439.4542;

console. log( numFormat(a)); // "1,234,567,894,532"

function name( params) {

var res = params. toString(). replace( / \d + /, function( n){

return n. replace( /( \d )(?=( \d {3} ) +$ )/ g, function ( $2) {

return $2 + ',';

})

})

return res ;

}

console. log( name(b)); // "673,439.4542"