網頁設計 : [分享]幾個常用的JavaScript小函數

function chknbr(num,opt1,opt2){
var i=num.length;var staus;
//staus用於記錄.的個數status=0;
if ((opt2!=1) && (num.charAt(0)=='-')){
//alert("You have enter a invalid number.");return 0;}
//當最後一位為.時出錯
if (num.charAt(i-1)=='.'){
//alert("You have enter a invalid number.");return 0;}
for (j=0;j<i;j++){
if (num.charAt(j)=='.'){status++;}
if (status1) {
//alert("You have enter a invalid number.");
return 0;        }
if (num.charAt(j)<'0' || num.charAt(j)'9' ){
if (((opt1==0) || (num.charAt(j)!='.')) && (j!=0)) {
//alert("You have enter a invalid number.");return 0;}}}return 1;}

function chkdate(datestr){
var lthdatestr
if (datestr != "")
lthdatestr= datestr.length ;else
lthdatestr=0;var tmpy="";
var tmpm="";var tmpd="";
//var datestr;var status;status=0;
if ( lthdatestr== 0)return 0
for (i=0;i<lthdatestr;i++)
{    if (datestr.charAt(i)== '-'){status++;}
if (status2){
//alert("Invalid format of date!");return 0;}
if ((status==0) && (datestr.charAt(i)!='-')){
tmpy=tmpy+datestr.charAt(i)}
if ((status==1) && (datestr.charAt(i)!='-')){
tmpm=tmpm+datestr.charAt(i)}
if ((status==2) && (datestr.charAt(i)!='-')){
tmpd=tmpd+datestr.charAt(i)}}
year=new String (tmpy);
month=new String (tmpm);
day=new String (tmpd)
//tempdate= new String (year+month+day);
//alert(tempdate);
if ((tmpy.length!=4) || (tmpm.length2) || (tmpd.length2)){
//alert("Invalid format of date!");return 0;}
if (!((1<=month) && (12=month) && (31=day) && (1<=day)) ){
//alert ("Invalid month or day!");return 0;}
if (!((year % 4)==0) && (month==2) && (day==29)){
//alert ("This is not a leap year!");return 0;}
if ((month<=7) && ((month % 2)==0) && (day=31)){
//alert ("This month is a small month!");return 0;}
if ((month=8) && ((month % 2)==1) && (day=31)){
//alert ("This month is a small month!");return 0;}
if ((month==2) && (day==30)){
//alert("The Febryary never has this day!");return 0;}return 1;}

function chksafe(a){    return 1;
/*    fibdn = new Array ("'" ,"\\", "、", ",", ";", "/");
i=fibdn.length;j=a.length;
for (ii=0;ii<i;ii++)
{    for (jj=0;jj<j;jj++)
{    temp1=a.charAt(jj);
temp2=fibdn[ii];
if (tem';p1==temp2)
{    return 0; }}}return 1;*/    }

function chkspc(a){
var i=a.length;var j = 0;
var k = 0;while (k<i){
if (a.charAt(k) != " ")j = j+1;k = k+1;}
if (j==0){return 0;}if (i!=j)
{ return 2; }else{return 1;}}