JavaScript - String For Phone Numbers

<script language="JavaScript">
function echeck(str) {

		var at="@"
		var dot="."
		var lat=str.indexOf(at)
		var lstr=str.length
		var ldot=str.indexOf(dot)
		if (str.indexOf(at)==-1){
		   alert("Please Enter a Valid E-mail")
		   return false
		}

		if (str.indexOf(at)==-1 || str.indexOf(at)==0 || str.indexOf(at)==lstr){
		   alert("Please Enter a Valid E-mail")
		   return false
		}

		if (str.indexOf(dot)==-1 || str.indexOf(dot)==0 || str.indexOf(dot)==lstr){
		    alert("Please Enter a Valid E-mail")
		    return false
		}

		 if (str.indexOf(at,(lat+1))!=-1){
		    alert("Please Enter a Valid E-mail")
		    return false
		 }

		 if (str.substring(lat-1,lat)==dot || str.substring(lat+1,lat+2)==dot){
		    alert("Please Enter a Valid E-mail")
		    return false
		 }

		 if (str.indexOf(dot,(lat+2))==-1){
		    alert("Please Enter a Valid E-mail")
		    return false
		 }
		
		 if (str.indexOf(" ")!=-1){
		    alert("Please Enter a Valid E-mail")
		    return false
		 }
		 

 		 return true					
	}

function validate_required(field,alerttxt)
{
with (field)
  {
  if (value==null||value=="")
    {
    alert(alerttxt);return false;
    }
  else
    {
    return true;
    }
  }
}
function validate_form(thisform)
{
with (thisform)
  {
  if (validate_required(Name,"Name must be filled out!")==false)
  {Name.focus();return false;}
  if (validate_required(Surname,"Surname must be filled out!")==false)
  {Surname.focus();return false;} 
  if (validate_required(Country,"Address must be filled out!")==false)
  {Country.focus();return false;}
  } 
  
  {
	var emailID=document.submitting.email
	
	if ((emailID.value==null)||(emailID.value=="")){
		alert("Please Enter a Valid E-mail")
		emailID.focus()
		return false
	}
	if (echeck(emailID.value)==false){
		emailID.value=""
		emailID.focus()
		return false
	}
	return true
 }
}

function verifyEmail(form) {
checkEmail = form.email.value

if ((checkEmail.indexOf('@') < 0) || ((checkEmail.charAt(checkEmail.length-4) != '.') && (checkEmail.charAt(checkEmail.length-3) != '.')))
{alert("You have entered an invalid email address. Please try again.");
form.email.select();
return false;
}

else {
form.method="get";
form.rel="nofollow" target="_self";
form.action="myscript.cgi";
form.submit();
}
}
</script>

        <form action="submit.htm" onsubmit="return validate_form(this)" method="post" name="submitting">
        <span class="style5">Select Plant:
        <form id="form1" name="form1" method="post" action="">
  <label>
            <select name="Item" id="Item">
              <option>OMGwoopwoop Plant</option>
              <option>I'm Blue Plant </option>
              <option>Anonymous Plant</option>
              <option>Rawr Plant</option>
              <option>Chicka Plant </option>
              <option>Fruitopola Plant</option>
              <option>Whitoe Plant</option>
              <option>Wukidoo Plant </option>
</select>
          </label>
        </p>
      <p>Name:<span class="style1"> 
        <input type="text" name="Name" size="30">
        <br>
        <br>
                </span>Surname:
        <span class="style1">
        <input type="text" name="Surname" size="30">
        <br>
        <br>
        </span>Address:<span class="style1">
         <input type="text" name="Country" size="30">
                        <br>
                        <br>
		</span>Email:<span class="style1">
        <input type="text" name="email" size="30">
                                <br></span></p>
        Phone Number:<span class="style1">
        <input type="text" name="phone" size="30">
      <form action="submit.htm" onSubmit="return validate_form(this)" method="post">
  <input type="submit" value="Submit">
</form>

function setUp(info) {
  var v = document.getElementById('phonesearch').selectedIndex.toString(); 
  var ln, fn, ext;
  var arr = new Array();
  var sel = document.getElementById('phonelist');
  for (var i = sel.options.length-1; i >= 0 ; i--) { sel.options[i] = null; }
  for(i = 0; i < phonelist.length; i++ ) {
	fn = phonelist[i][0];
	ln = phonelist[i][1];
	ext= phonelist[i][2]; 
	switch (v) { 
//	  case "1" : zo = ln+', '+fn;  zv = zo +' : '+ext; break;
	  case "2" : zo = fn+' '+ln;   zv = zo +' : '+ext; break;
	  case "3" : zo = ext+' : '+ln+', '+fn;  zv = zo;  break;
	  default:   zo = ln+', '+fn;  zv = zo +' : '+ext; break;
    }  
    if (info != '') {
      if (zo.toUpperCase().indexOf(info.toUpperCase(),0) == 0) { arr.push(zo+'||'+zv); }
    } else { arr.push(zo+'||'+zv); }
  }
  arr.sort();	// Like the original order, comment out this line!
  var z = [];
  for (i=0; i<arr.length; i++) {
	z = arr[i].split('||');
    sel.options[i] = new Option(z[0],z[1],false,false);
  }  
  var z = 13;  if (phonelist.length < z) { z = phonelist.length; }
  sel.size = z;
  if (info == '') { sel.focus(); }
}

<form name="menuform" onSubmit="return false">
  <p class="style1">Select to search by first name, last name, or extension. Then click in the text box on the bottom and type in the first few letters of who/what it is you're looking for.</p>
<p class="style1">Then, simply click the entry you need.</p>
<select id="phonesearch" onchange="setUp('')" size="4">
  <option value=""><i>Choose one</i></option>
  <option value="1">Last name</option>
  <option value="2" selected>First name</option>
  <option value="3">Extension</option>
</select>
<br /><br />
<select id="phonelist" onclick="alert(this.value)"></select>
<br /><br />
<input type="text" id="srch" value="" onkeyup="setUp(this.value)" size="20">
<br /><a href="#"
 onclick="sel=document.getElementById('srch');sel.value='';setUp('');sel.focus()">Search Clear</a>
</form>

^[0]{1}\d{2,4}\s|-{1}\d|\s|-{6,9}$

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml" >
<head>
    <title>Untitled Page</title>
    <script type='text/javascript' language="javascript">

var validPhoneChar = "+";
// Minimum no of digits in an international phone no.
var minDigitsInPhoneNumber = 10;

function isInteger(s)
{   
    var i;
    for (i = 0; i < s.length; i++)
    {   
        // Check that current character is a number.
        var c = s.charAt(i);
        if (((c < "0") || (c > "9"))) 
            return false;
    }
    // All characters are numbers.
    return true;
}

function stripCharsInBag(s, bag)
{   
    var i;
    var returnString = "";
    // Search through string's characters one by one.
    // If character is not in bag, append to returnString.
    for (i = 0; i < s.length; i++)
    {   
        // Check that current character isn't whitespace.
        var c = s.charAt(i);
        if (bag.indexOf(c) == -1) returnString += c;
    }
    return returnString;
}

function checkRequirements(strPhone)
{
    if(strPhone.indexOf("+") > 1)
        return false;
    s = stripCharsInBag(strPhone,validPhoneChar);
    return (isInteger(s) && s.length >= minDigitsInPhoneNumber);
}

function ValidateForm()
{
    var Phone = document.getElementById("Text1");
    //var Phone1 = document.getElementById("Text23");
    if ((Phone.value == null)||(Phone.value == "")) //if match failed
    {
        alert("Please Enter your Phone Number.");
        Phone.focus();
            return false;
    }
    /*if ((Phone1.value == null)||(Phone1.value == "")) //if match failed
    {
        alert("Please Enter your Phone Number0.");
        Phone.focus();
            return false;
    }*/    
    if (checkRequirements(Phone.value) == false)
    {
        alert("Please Enter a Valid Phone Number.");
        Phone.value = "";
        Phone.focus();
            return false;
    }
    else    
        alert("YAY!");
    return true;
 }    
    
    
function NotAllowSpace()
{
    // Get the ASCII value of the key that the user entered
    var key = window.event.keyCode;

    // Verify if the key entered was a Space
    if ( key == 32 )
    {
        // If it was, then dispose the key and continue with entry
        window.event.returnValue = null; 
        alert("Invalid,Please check")
    }
    
    else
        // If it was not, then allow the entry to continue
        return;

}
    </script>
</head>
<body>
<label>Office Telephone:</label>
<input id="Text1" type="text" onkeydown = "return (event.keyCode != 32)"/><br />
<input id="Button1" type="button" value="button" onclick="return ValidateForm();" /><br />

</body>
</html>

else if(fieldType == 'phone')
				{	
					if((required == 1 && fieldObj.value=='')  ||  (fieldObj.value!=''  && !validate_phone(fieldObj.value)))
					{				
						fieldObj.setAttribute("class","mainFormError");
						fieldObj.setAttribute("className","mainFormError");
						fieldObj.focus();
						return false;					
					}

				}



				function validate_phone(phoneStr)
			{		
				apos=phoneStr.indexOf("@");
				

				if (apos<1||dotpos-apos<2) 
				{
					return false;
				}
				else
				{
					return true;
				}
			}

	<form id="contactform" action="contact-submit.php" method="post">

			<!-- form fields -->
			<div class="form">
			<label for="name">Name<em>&bull;</em></label>
			<input class="textbox required" type="text" name="name" id="name" /><br />


			<label for="email">E-Mail<em>&bull;</em></label>
			<input class="textbox required email" type="text" name="email" id="email" /><br />

	<body>
		<select>
			<option value="createMsg">Add Message</option>
			<option value="removeMsg">Remove Message</option>
		</select>
	</body>

var menu = {
	handleMenu : function(callback){
 	   	if(callback === "string"){
			menu[callback]();
		}
 		else {
			console.log("Issue occurred")
		}
 		
	},
	createMsg : function(){
		var	content = document.createTextNode("Please give additional information."),
			heading = document.createElement("h1");

		heading.appendChild(content);
		document.body.appendChild(heading);

	},
	removeMsg : function(){
		
	}
}
 
document.getElementsByTagName('select')[0].onchange = function(){ menu.handleMenu(this.value)};

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml" >
<head>
    <title>Untitled Page</title>
    <link rel="stylesheet" type="text/css" href="CSS files/specialAlignment.css" />
    <link rel="stylesheet" type="text/css" href="CSS files/externalCSS.css"/>    
    <script language = "javascript" type = "text/javascript">
    
function check() 
{
    var fields = new Array("Office Telephone", "Mobile Telephone","Fax Number");
    var telnr = /(^[\+]?[\d]{8,20}$)/;

    var index = new Array();  
    for(var i = 0; i < fields.length; i++)  
    {  
        var arrayFields = document.getElementsByName(fields[i]);  
        for(var j = 0; j < arrayFields.length; j++)  
        if(!(arrayFields[j].value) == "")  
        {   
            arrayFields[j].className = "defaultColor";              
        }  
        
        else  
        {  
            arrayFields[j].className ="changeToRed"; 
            index.push(fields[i]);                  
        }        
    }  
    
    if(index != 0)  
    {  
        joinComma = index.join(', ');  
        alert('The field(s) corresponding to '+ joinComma + ' is/are not filled in.');   
    }  
         
}  

function noSpace(e, dec)
{
    var key;
    var keychar;

    if (window.event) 
    {
       key = window.event.keyCode;
    }
    else if (e) 
    {
       key = e.which;
    }
    else 
    {
       return true;
    }
    keychar = String.fromCharCode(key);

    if ((key==null) || (key==0) || (key==8) ||  (key==9) || (key==13) || (key==27) /*|| (key==107)*/) 
    {
       return true;
    }
    else if ((("0123456789").indexOf(keychar) > -1)&& check(telnr.test(tfld))) 
    {
       return true;
    }
    else if (dec && (keychar == ".")) 
    { 
      return true;
    }
    else
       return false;
        
} 
    </script>
</head>
<body>
                        <label>
                            *Office Telephone:</label>
                        <input id="Text16" type="text" name="Office Telephone" onkeydown="return noSpace(event)" />
                        <br />
                        <br />
                        <label>
                            *Mobile Telephone:</label>
                        <input id="Text17" type="text" name="Mobile Telephone" onkeydown="return noSpace(event)" /><br />
                        <br />
                        <label>
                            *Fax Number:</label>
                        <input id="Text18" type="text" name="Fax Number" onkeydown="return noSpace(event)" />
                        <br />
                        <br />
                <input id="Submit17" type="submit" value="Submit" onclick="return check()"/>
 
</body>
</html>

<html>
    <head>
        <title></title>
        <meta http-equiv="Content-Type" content="text/html; charset=UTF-8">

        <SCRIPT type="text/javascript">
     
            function isNumberKey1(evt)
            {
                var charCode = (evt.which) ? evt.which : event.keyCode
                if (charCode = 46 && charCode > 31 
                    && (charCode < 48 || charCode > 57))
                    return false;

                return true;
            }
     
    
     
        </SCRIPT>
    </head>
    <body>
        Phone number :
        <input type="text" id="phonenumber" onkeypress="return isNumberKey1(event)"  maxlength="10" size="15" > <br /> <br />
        Alternative number: 
        <input type="text" onkeypress="return isNumberKey1(event)" id="alt" maxlength="10" size="15">
         <input type="button"  value="Submit">

    </body>
</html>

<html>
<head>
<script type="text/javascript">

var varX = user input;
function sum() {
   var varX = user input;
   for(varY = 1; varY<=10; varY++) {
      varX = varX + varY;
   }
   return varX;
}

var resultat = sum();
alert(resultat);         // show message box with result
</script>
</head>
<body>
</body>
</html>