Javascript verification can only enter numbers and a decimal point

Functiongaga (obj) {value allows you to enter a decimal point and number objvalueobjvaluereplace ([^ d] g, & quot;); replace all non-numbers first, in addition to numbers and objvalueobjvaluereplace (^ g, & quot;); function gaga (obj) {// a decimal point and number obj are allowed. value = obj. value. replace (/[^ \ d.] /g, ""); // replace all the non-numeric values, except the numbers and. obj. value = obj. value. replace (/^ \. /g, ""); // The first one must be a number instead of a number. obj. value = obj. value. replace (/\. {2,}/g ,". "); // ensure that only one exists. no. obj. value = obj. value. replace (". "," $ # $ "). replace (/\. /g ,""). replace ("$ # $ ",". "); // guarantee. only appears once, but not more than twice}