常用javascript函数(一)

/*********************************************************************************
*    FUNCTION:        isBetween
*    PARAMETERS:        val        AS any value
*                    lo        AS Lower limit to check
*                    hi        AS Higher limit to check
*    CALLS:            NOTHING
*    RETURNS:        TRUE if val is between lo and hi both inclusive, otherwise false.
**********************************************************************************/
function isBetween (val, lo, hi) {
    if ((val < lo) || (val > hi)) { return(false); }
    else { return(true); }
}

/*********************************************************************************
*    FUNCTION:        isDate checks a valid date
*    PARAMETERS:        theStr        AS String
*    CALLS:            isBetween, isInt
*    RETURNS:        TRUE if theStr is a valid date otherwise false.
**********************************************************************************/
function isDate (theStr) {
    var the1st = theStr.indexOf(@#-@#);
    var the2nd = theStr.lastIndexOf(@#-@#);
    
    if (the1st == the2nd) { return(false); }
    else {
        var y = theStr.substring(0,the1st);
        var m = theStr.substring(the1st+1,the2nd);
        var d = theStr.substring(the2nd+1,theStr.length);
        var maxDays = 31;
        
        if (isInt(m)==false || isInt(d)==false || isInt(y)==false) {
            return(false); }
        else if (y.length < 4) { return(false); }
        else if (!isBetween (m, 1, 12)) { return(false); }
        else if (m==4 || m==6 || m==9 || m==11) maxDays = 30;
        else if (m==2) {
            if (y % 4 > 0) maxDays = 28;
            else if (y % 100 == 0 && y % 400 > 0) maxDays = 28;
               else maxDays = 29;
        }
        if (isBetween(d, 1, maxDays) == false) { return(false); }
        else { return(true); }
    }
}
/*********************************************************************************
*    FUNCTION:        isEuDate checks a valid date in British format
*    PARAMETERS:        theStr        AS String
*    CALLS:            isBetween, isInt
*    RETURNS:        TRUE if theStr is a valid date otherwise false.
**********************************************************************************/
function isEuDate (theStr) {
    if (isBetween(theStr.length, 8, 10) == false) { return(false); }
    else {
        var the1st = theStr.indexOf(@#/@#);
        var the2nd = theStr.lastIndexOf(@#/@#);
        
        if (the1st == the2nd) { return(false); }
        else {
            var m = theStr.substring(the1st+1,the2nd);
            var d = theStr.substring(0,the1st);
            var y = theStr.substring(the2nd+1,theStr.length);
            var maxDays = 31;

            if (isInt(m)==false || isInt(d)==false || isInt(y)==false) {
                return(false); }
            else if (y.length < 4) { return(false); }
            else if (isBetween (m, 1, 12) == false) { return(false); }
            else if (m==4 || m==6 || m==9 || m==11) maxDays = 30;
            else if (m==2) {
                if (y % 4 > 0) maxDays = 28;
                else if (y % 100 == 0 && y % 400 > 0) maxDays = 28;
                else maxDays = 29;
            }
            
            if (isBetween(d, 1, maxDays) == false) { return(false); }
            else { return(true); }
        }
    }
    
}
/********************************************************************************
*   FUNCTION:       Compare Date! Which is the latest!
*   PARAMETERS:     lessDate,moreDate AS String
*   CALLS:          isDate,isBetween
*   RETURNS:        TRUE if lessDate<moreDate
*********************************************************************************/
function isComdate (lessDate , moreDate)
{
    if (!isDate(lessDate)) { return(false);}
    if (!isDate(moreDate)) { return(false);}
    var less1st = lessDate.indexOf(@#-@#);
    var less2nd = lessDate.lastIndexOf(@#-@#);
    var more1st = moreDate.indexOf(@#-@#);
    var more2nd = moreDate.lastIndexOf(@#-@#);
    var lessy = lessDate.substring(0,less1st);
    var lessm = lessDate.substring(less1st+1,less2nd);
    var lessd = lessDate.substring(less2nd+1,lessDate.length);
    var morey = moreDate.substring(0,more1st);
    var morem = moreDate.substring(more1st+1,more2nd);
    var mored = moreDate.substring(more2nd+1,moreDate.length);
    var Date1 = new Date(lessy,lessm,lessd);
    var Date2 = new Date(morey,morem,mored);
    if (Date1>Date2) { return(false);}
     return(true);
        
}

/*********************************************************************************
*    FUNCTION    isEmpty checks if the parameter is empty or null
*    PARAMETER    str        AS String
**********************************************************************************/
function isEmpty (str) {
    if ((str==null)||(str.length==0)) return true;
    else return(false);
}

/*********************************************************************************
*    FUNCTION:        isInt
*    PARAMETER:        theStr    AS String
*    RETURNS:        TRUE if the passed parameter is an integer, otherwise FALSE
*    CALLS:            isDigit
**********************************************************************************/
function isInt (theStr) {
    var flag = true;

    if (isEmpty(theStr)) { flag=false; }
    else
    {    for (var i=0; i<theStr.length; i++) {
            if (isDigit(theStr.substring(i,i+1)) == false) {
                flag = false; break;
            }
        }
    }
    return(flag);
}

/*********************************************************************************
*    FUNCTION:        isReal
*    PARAMETER:    heStr    AS String
                        decLen    AS Integer (how many digits after period)
*    RETURNS:        TRUE if theStr is a float, otherwise FALSE
*    CALLS:            isInt
**********************************************************************************/
function isReal (theStr, decLen) {
    var dot1st = theStr.indexOf(@#.@#);
    var dot2nd = theStr.lastIndexOf(@#.@#);
    var OK = true;
    
    if (isEmpty(theStr)) return false;

    if (dot1st == -1) {
        if (!isInt(theStr)) return(false);
        else return(true);
    }
    
    else if (dot1st != dot2nd) return (false);
    else if (dot1st==0) return (false);
    else {
        var intPart = theStr.substring(0, dot1st);
        var decPart = theStr.substring(dot2nd+1);

        if (decPart.length > decLen) return(false);
        else if (!isInt(intPart) || !isInt(decPart)) return (false);
        else if (isEmpty(decPart)) return (false);
        else return(true);
    }
}

/*********************************************************************************
*    FUNCTION:        isEmail
*    PARAMETER:        String (Email Address)
*    RETURNS:        TRUE if the String is a valid Email address
*                    FALSE if the passed string is not a valid Email Address
*    EMAIL FORMAT:    AnyName@EmailServer e.g; webmaster@hotmail.com
*                    @ sign can appear only once in the email address.
*********************************************************************************/
function isEmail (theStr) {
    var atIndex = theStr.indexOf(@#@@#);
    var dotIndex = theStr.indexOf(@#.@#, atIndex);
    var flag = true;
    theSub = theStr.substring(0, dotIndex+1)

    if ((atIndex < 1)||(atIndex != theStr.lastIndexOf(@#@@#))||(dotIndex < atIndex + 2)||(theStr.length <= theSub.length))
    {    return(false); }
    else { return(true); }
}
/*********************************************************************************
*    FUNCTION:        newWindow
*    PARAMETERS:        doc         ->    Document to open in the new window
                    hite     ->    Height of the new window
                    wide     ->    Width of the new window
                    bars    ->    1-Scroll bars = YES 0-Scroll Bars = NO
                    resize     ->    1-Resizable = YES 0-Resizable = NO
*    CALLS:            NONE
*    RETURNS:        New window instance
**********************************************************************************/
function newWindow (doc, hite, wide, bars, resize) {
    var winNew="_blank";
    var opt="toolbar=0,location=0,directories=0,status=0,menubar=0,";
    opt+=("scrollbars="+bars+",");
    opt+=("resizable="+resize+",");
    opt+=("width="+wide+",");
    opt+=("height="+hite);
    winHandle=window.open(doc,winNew,opt);
    return;
}
/*********************************************************************************
*    FUNCTION:        DecimalFormat
*    PARAMETERS:        paramValue -> Field value
*    CALLS:                NONE
*    RETURNS:        Formated string
**********************************************************************************/
function DecimalFormat (paramValue) {
    var intPart = parseInt(paramValue);
    var decPart =parseFloat(paramValue) - intPart;

    str = "";
    if ((decPart == 0) || (decPart == null)) str += (intPart + ".00");
    else str += (intPart + decPart);
    
    return (str);
}

原文转自：http://www.ltesting.net