/** Calculate middle european summertime */
function utc_to_local_time($timestamp,$offset=0,$summertime=true) { 
	 $year = strftime("%Y", $timestamp); 
	$timestamp += (3600*intval($offset)); // add local offset
	
	// Calculate beginning and end of Summertime
	$initTime = mktime(2,0,0,3,31-date('w', mktime(2,0,0,3,31,$year)),$year); 
	$endTime = mktime(2,0,0,10,31-date('w', mktime(2,0,0,10,31,$year)),$year); 

    // Check if summertime, return adequatly
    if (($timestamp > $initTime && $timestamp < $endTime) && $summertime) { 
        return ($timestamp + 3600); 
    } else { 
        return ($timestamp); 
    } 
}

// example: Austria time
echo date("d.m.Y, H:i",utc_to_local_time($utc_time,1);

Note: Since jQuery is that popular today, it is possibly better to use this (see jQuery Ajax Tutorial).

var XMLHTTP = null;

function AjaxRequest(compString) {

// XMLHTTP-Request Objekt erzeugen, dabei auf Browserkonformität achten
	if(window.XMLHttpRequest) {
		XMLHTTP = new XMLHttpRequest();
	} else if(window.ActiveXObject) {
		try {
			XMLHTTP = new ActiveXObject("Msxml2.XMLHTTP");
		} catch(ex) {
			try {
				XMLHTTP = new ActiveXObject("Microsoft.XMLHTTP");
			} catch(ex) {
			}
		}
	}
	
	XMLHTTP.open("GET","test.php?compString="+compString);
	XMLHTTP.onreadystatechange = MyRequestExecute;
	XMLHTTP.send(null);
}

// wird jedes mal aufgerufen, wenn der XMLHTTP-Request eine neue Stufe erreicht, bei 4 ist die Antwort des Servers eingetroffen
function MyRequestExecute() {
	// responseText als Javascript-String, responseXML als Javascript XML-DOM-Element, status Statuscode, statusText des. Beschreibung
	if(XMLHTTP.readyState == 4) {
		document.getElementById("result").innerHTML = XMLHTTP.responseText;
	}
}

The server side

query($sql);
	
} catch (Exception $e) {
    echo 'Verbindungsaufbau fehlgeschlagen: ',  $e->getMessage(), "\n";
}

echo $_GET['compString']."< pre >".$horst."";
?>

Have fun an use wisely.

1. Get Elements By Class Name (getElementsByClassName)

This is maybe one of the most used and most needed custom Javascript functions of all time. It provides a way to get all elements in a page with a certain class attribute.

function getElementsByClassName(classname, node){
    if (!node) {
        node = document.getElementsByTagName('body')[0];
    }
 
    var a = [], re = new RegExp('\\b' + classname + '\\b');
    els = node.getElementsByTagName('*');
    for (var i = 0, j = els.length; i < j; i++) {
        if (re.test(els[i].className)) {
            a.push(els[i]);
        }
    }
    return a;
}

2. Test if Internet Explorer is used and get its version number

I do not know how much functions, CSS selectors or whatever - IE so often acts different or just stupid. It always requires extra work. This after all will help you to detect this nasty browser.

// use the class
if(Browser.Version() <8) {
	// make crazy IE shit
}
 
var Browser = {
    Version: function(){
        var version = 999; // we assume a sane browser
        if (navigator.appVersion.indexOf("MSIE") != -1) 
            // bah, IE again, lets downgrade version number
            version = parseFloat(navigator.appVersion.split("MSIE")[1]);
        return version;
    }
}

3. Clear input-field onclick, if value is default

This is not much of javascript, we actually call it dynamic html. It is just the standard way to present the comfortable input fields to users.

4. Test if a String is not empty

Can help to avoid a lot of common mistakes with javascript.

var bpat    = /\S/;
function isNonblank (s) {
   return String (s).search (bpat) != -1
}

5. Function Exists

This is a possibility in Javascript to test if a function exists (like function_exists in PHP). This can be useful in cases of debugging or when you are not sure if some required script file is loaded, for example.

if(typeof yourFunctionName == 'function') {
     yourFunctionName();
}

6. Get scroll width/height of page visitors' browser window

A browser-safe way to get the number of pixels, which a user scrolled down the webpage currently.

function getScrollXY() {
    var scrOfX = 0, scrOfY = 0;
 
    if( typeof( window.pageYOffset ) == 'number' ) {
        //Netscape compliant
        scrOfY = window.pageYOffset;
        scrOfX = window.pageXOffset;
    } else if( document.body && ( document.body.scrollLeft || document.body.scrollTop ) ) {
        //DOM compliant
        scrOfY = document.body.scrollTop;
        scrOfX = document.body.scrollLeft;
    } else if( document.documentElement && ( document.documentElement.scrollLeft || document.documentElement.scrollTop ) ) {
        //IE6 standards compliant mode
        scrOfY = document.documentElement.scrollTop;
        scrOfX = document.documentElement.scrollLeft;
    }
    return [ scrOfX, scrOfY ];
}

7. Get current size of page visitors' browser window

A browser-safe way to get the window height and window width of the current viewers browser in pixels.

function getWindowSize() {
    var myWidth = 0, myHeight = 0;
 
    if( typeof( window.innerWidth ) == 'number' ) {
        //Non-IE
        myWidth = window.innerWidth;
        myHeight = window.innerHeight;
    } else if( document.documentElement && ( document.documentElement.clientWidth || document.documentElement.clientHeight ) ) {
        //IE 6+ in 'standards compliant mode'
        myWidth = document.documentElement.clientWidth;
        myHeight = document.documentElement.clientHeight;
    } else if( document.body && ( document.body.clientWidth || document.body.clientHeight ) ) {
        //IE 4 compatible
        myWidth = document.body.clientWidth;
        myHeight = document.body.clientHeight;
    }
    return [ myWidth, myHeight ];
}

8. Scale images by setting a maximum width/height

It is not always the best idea to scale images with javascript. But I came to several applications there this was useful though.

var images = document.getElementsByTagName("img"); // get your images somehow
scaleImages(imgs,150,150); // call the function
         
// scales the images to a maximum width/height
function scaleImages(images,maxh,maxw) {
  
for(i=0;i ratio){
		// height is the problem
		if (img.height > maxh){
			img.width = Math.round(img.width*(maxh/img.height));
			img.height = maxh;
		}
	} else {
		// width is the problem
		if (img.width > maxh){
			img.height = Math.round(img.height*(maxw/img.width));
			img.width = maxw;
		}
	  }
	  img.setAttribute("class","showpreview ready");
  }
}

9. Print Javascript Array (like print_r()-in PHP)

A really useful function for debugging and developing with javascript. Instead of [object Object] or something similar you will see the whole contents of an array in your output.

	function dump(arr,level) {
		var dumped_text = "";
		if(!level) level = 0;
		
		//The padding given at the beginning of the line.
		var level_padding = "";
		for(var j=0;j \"" + value + "\"\n";
				}
			}
		} else { //Stings/Chars/Numbers etc.
			dumped_text = "===>"+arr+"<===("+typeof(arr)+")";
		}
		return dumped_text;
	}

10. XML2Array (parse xml to javascript array)

For the special case of reading XML with Javascript. But very useful, when it comes to the case. It is much easier to handle a huge array in Javascript than reading lots of data from a complex XML-file. Maybe there is a tiny disadvantage concerning speed, but I think it is worth that.

//////////////////////////////////// xml2array() ////////////////////////////////////////
// See http://www.openjs.com/scripts/xml_parser/
var not_whitespace = new RegExp(/[^\s]/); //This can be given inside the funciton - I made it a global variable to make the scipt a little bit faster.
var parent_count;
//Process the xml data
function xml2array(xmlDoc,parent_count) {
	var arr;
	var parent = "";
	parent_count = parent_count || new Object;

	var attribute_inside = 0; /*:CONFIG: Value - 1 or 0
	*	If 1, Value and Attribute will be shown inside the tag - like this...
	*	For the XML string...
	*	http://www.bin-co.com/
	*	The resulting array will be...
	*	array['guid']['value'] = "http://www.bin-co.com/";
	*	array['guid']['attribute_isPermaLink'] = "true";
	*	
	*	If 0, the value will be inside the tag but the attribute will be outside - like this...	
	*	For the same XML String the resulting array will be...
	*	array['guid'] = "http://www.bin-co.com/";
	*	array['attribute_guid_isPermaLink'] = "true";
	*/

	if(xmlDoc.nodeName && xmlDoc.nodeName.charAt(0) != "#") {
		if(xmlDoc.childNodes.length > 1) { //If its a parent
			arr = new Object;
			parent = xmlDoc.nodeName;
			
		}
	}
	var value = xmlDoc.nodeValue;
	if(xmlDoc.parentNode && xmlDoc.parentNode.nodeName && value) {
		if(not_whitespace.test(value)) {//If its a child
			arr = new Object;
			arr[xmlDoc.parentNode.nodeName] = value;
		}
	}

	if(xmlDoc.childNodes.length) {
		if(xmlDoc.childNodes.length == 1) { //Just one item in this tag.
			arr = xml2array(xmlDoc.childNodes[0],parent_count); //:RECURSION:
		} else { //If there is more than one childNodes, go thru them one by one and get their results.
			var index = 0;

			for(var i=0; i2) break;//We just need to know wether it is a single value array or not
					}

					if(assoc && arr_count == 1) {
						if(arr[key]) { 	//If another element exists with the same tag name before,
										//		put it in a numeric array.
							//Find out how many time this parent made its appearance
							if(!parent_count || !parent_count[key]) {
								parent_count[key] = 0;

								var temp_arr = arr[key];
								arr[key] = new Object;
								arr[key][0] = temp_arr;
							}
							parent_count[key]++;
							arr[key][parent_count[key]] = temp[key]; //Members of of a numeric array
						} else {
							parent_count[key] = 0;
							arr[key] = temp[key];
							if(xmlDoc.childNodes[i].attributes && xmlDoc.childNodes[i].attributes.length) {
								for(var j=0; j
]]>
					
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			0
		
		
			
		
		
		https://blog.blackbam.at/2011/06/27/wordpress-improved-user-search-first-name-last-name-email-in-backend/
					https://blog.blackbam.at/2011/06/27/wordpress-improved-user-search-first-name-last-name-email-in-backend/#comments
		
		
		Mon, 27 Jun 2011 22:35:01 +0000
				
		
		
		
		
		
		
		https://blog.blackbam.at/?p=1457

					
										Recently, when working on a WordPress website for a huge amount of users, a customer was unsatisfyied with the WordPress backend search for users. The default backend search only is searching for your search string in usernames, but not for first name, last name or email of users.

 
As most WordPress projects are barely designed to have a huge amoung of users, this is not necessary in most cases. Anyway, the following code will help with this problem – add this to your functions.php-file and the WordPress user search will scan first name, last name and e-mail of every user.
 
Download the official WordPress Plugin
How the Plugin basically works (code overview of Version 1.2)
 
   // the actual improvement of the query
    function user_search_by_multiple_parameters($wp_user_query) {
        if(false === strpos($wp_user_query -> query_where, '@') && !empty($_GET["s"])) {

            global $wpdb;

            $uids=array();

			// get the custom meta fields to search
			$iusib_custom_meta = get_option('iusib_meta_fields');
			$iusib_cma = array_map('trim', explode(",",$iusib_custom_meta));

			$iusib_add = "";
			// the escaped query string
			$qstr = mysql_real_escape_string($_GET["s"]);
			
			// add all custom fields into the query
			if(!empty($iusib_cma)) {
				$iusib_add = " OR meta_key='".implode("' OR meta_key='",$iusib_cma)."'";
			}

            $usermeta_affected_ids = $wpdb -> get_results("SELECT DISTINCT user_id FROM ".$wpdb->base_prefix."usermeta WHERE (meta_key='first_name' OR meta_key='last_name'".$iusib_add.") AND LOWER(meta_value) LIKE '%".$qstr."%'");

            foreach($usermeta_affected_ids as $maf) {
                array_push($uids,$maf->user_id);
            }

            $users_affected_ids = $wpdb -> get_results("SELECT DISTINCT ID FROM ".$wpdb->base_prefix."users WHERE LOWER(user_nicename) LIKE '%".$qstr."%' OR LOWER(user_email) LIKE '%".$qstr."%'");

            foreach($users_affected_ids as $maf) {
                if(!in_array($maf->ID,$uids)) {
                    array_push($uids,$maf->ID);
                }
            }
			
            $id_string = implode(",",$uids);

            $wp_user_query -> query_where = str_replace("user_nicename LIKE '%".$qstr."%'", "ID IN(".$id_string.")", $wp_user_query -> query_where);
        }
        return $wp_user_query;
    }


]]>
					
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			74
		
		
			
		
		
		https://blog.blackbam.at/2010/10/18/scroll-a-very-big-database-table-with-ajax/
					https://blog.blackbam.at/2010/10/18/scroll-a-very-big-database-table-with-ajax/#respond
		
		
		Mon, 18 Oct 2010 16:56:41 +0000
				
		
		
		
		http://www.blackbam.at/blog/?p=885

					
										This tutorial shows how it is possible to scroll a very big database table using Asynchronous Javascript and JSON with an easy extendable and customizable script. We created four files – index.html (contains the Ajax table), functions.js (contains all the Ajax work), suggest.php (the server-side work), and entries.php (server-side script for instantiating number of table values). There is also a dummy file to create and fill the database with values fast, which is called “createTable.php”.





Watch the example here




Function: When a user types in a certain pattern, the twenty nearest values are fetched from the database. When a user scrolls the table, the values are fetched depending on the position of the cursor or by fetching the next or previous entries from the database.




index.html



    
        
        
        
    
    
        
Demonstration
        
Shows how to get an fast and precise result from scrolling a big table using Asynchronous Javascript with JSON.
        

		

		

	        

	            

	                
	            
	            

	                previous 20
	                
 
	                next 20
	            
				

					
Collected values
				
				

	        

	        

			
Search for a specific pattern:
			
			
			
			
			
		

        
    






functions.js
/**
 * @author Blackbam
 */
var XMLHTTP = null;
var onetime = 1;
var onetime2 = 1;

// Server-Request for data depending on parameters
function make_suggestion(compValue, how){

    if (how == "string") {
        document.getElementById("mode").value = "string";
    }

    // instantiate browser-independent XMLHttpRequest
    if (window.XMLHttpRequest) {
        XMLHTTP = new XMLHttpRequest();
    } else if (window.ActiveXObject) {
            try {
                XMLHTTP = new ActiveXObject("Msxml2.XMLHTTP");
            } catch (ex) {
                try {
                    XMLHTTP = new ActiveXObject("Microsoft.XMLHTTP");
                } catch (ex) {
                }
            }
        }
	
    if (how == "entries") {
		// Get the whole number of entries when loading the page
		var scrHeight = document.getElementById("gscr").style.height;
        XMLHTTP.open("GET", "entries.php?height="+scrHeight);
        XMLHTTP.onreadystatechange = setEntries;
    } else {
        if (how == "string" && compValue == "") {
            document.getElementById("current").value = 1;
			numeric_request();
        } else {
                XMLHTTP.open("GET", "suggest.php?compValue=" + compValue + "&how=" + how);
                XMLHTTP.onreadystatechange = MyRequestExecute;
        }
    }
    XMLHTTP.send(null);
}

// is called when the Server-Request reaches a new state
function MyRequestExecute(){
	// the answer from the server is hier when the XMLHTTP.readyState = 4
    if (XMLHTTP.readyState == 4) {
		
		// remove old entries from the table
		var cell = document.getElementById("result");
		if ( cell.hasChildNodes() ){
		    while ( cell.childNodes.length >= 1 ) {
		        cell.removeChild( cell.firstChild );       
		    } 
		}
		
		// Create a valid table content with the Jason-object
		var obj=eval('('+XMLHTTP.responseText+')');
		for(val in obj){
			var tr = cell.appendChild(document.createElement("tr"));
			var td = tr.appendChild(document.createElement("td"));
			td.setAttribute("onclick","javascript:collect(this.firstChild.nodeValue);");
			td.appendChild(document.createTextNode(obj[val]));
		}
		
		// if first time, display the table to the user now
		if (onetime2 == 1) {
			document.getElementById("loading").style.display = "none";
			document.getElementById("container").style.display = "block";
			onetime2 = 0;
		}
    }
}

// this function is called when the page is loaded first
function setEntries(){
	
	// when the server answers the number of table entries
    if (XMLHTTP.readyState == 4) {
		if (onetime == 1) {
			onetime = 0;
			var entries = XMLHTTP.responseText;
			document.getElementById("allEntries").value = entries;
			
			// a little hack: create as many 1px-divs as there are entries in the database
			for (i = 0; i <= entries; i++) {
				document.getElementById("gscr").appendChild(document.createElement("div"));
			}
			
			// now fill the table
			numeric_request();
		}
    }
}

// is used if a user scrolls the table using the scrollbar
function scrAction() {
	// alert(document.getElementById("gscr").scrollTop+1);
	document.getElementById("current").value=(document.getElementById("gscr").scrollTop+1);
	numeric_request();
}

// is called every time a user scrolls the table
function numeric_request(){
	document.getElementById("mode").value = "number";
	var startentry = document.getElementById("current").value;
	make_suggestion(startentry, "number");
}

// is called if a user scrolls the table by previous and next entries
function scroll(wohin){
	
	var curEntr = document.getElementById("current");
	var scrollbar = document.getElementById("gscr");

	var scrval = parseInt(curEntr.value);
	var allEntries = parseInt(document.getElementById("allEntries").value);
	
	if(wohin == 'u'){
		if(scrval < 20) {
			curEntr.value = 1;
			scrollbar.scrollTop = 1;
		} else {
			curEntr.value = (scrval-19);
			scrollbar.scrollTop = (scrval-19);
		}
	} else {
		var scrHeight = parseInt(document.getElementById("gscr").style.height)-2;
		var whole = parseInt(allEntries-scrHeight);
		if(scrval >= whole) {
			curEntr.value = whole;
			scrollbar.scrollTop = whole;
		} else {
			curEntr.value = (scrval+19);
			scrollbar.scrollTop = (scrval+19);
		}
	}
	numeric_request();
}

// stores the values the user has clicked
function collect(value) {
	document.getElementById("collection").appendChild(document.createTextNode(value));
	document.getElementById("collection").appendChild(document.createElement("br"));
}





suggest.php
query($sql) as $row) {
        $result_string[$i] = $row['random_word'];
		$i++;
    }

}
catch(PDOException $e) {
    echo $e->getMessage();
}

echo json_encode($result_string);

?>





entries.php
query($sql)->fetchAll())+$height;

}
catch(PDOException $e) {
    echo $e->getMessage();
}

echo $result_string;

?>





The dummy – createTable.php
/*** mysql hostname ***/
$hostname = 'localhost';

/*** mysql username ***/
$username = 'root';

/*** mysql password ***/
$password = '';

try {
    $db = new PDO("mysql:host=$hostname;dbname=meta", $username, $password);

    for ($i = 0; $i < 12000; $i++) {
        $random_word = randWord();
        try {
            $db->exec("INSERT INTO meta(random_word) VALUES ('$random_word')");
        }
        catch(PDOException $e) {
            echo "Eintrag ".$random_word." konnte nicht geschrieben werden. 
";
        }
    }

}
catch(PDOException $e) {
    echo $e->getMessage();
}

function randWord() {
    $length = rand(5, 15);
    $characters = "abcdefghijklmnopqrstuvwxyz";
    $string = "";

    for ($p = 0; $p < $length; $p++) {
        $string .= $characters[mt_rand(0, strlen($characters))];
    }

    return $string;
}

echo "It is finally done without crashing the server!";

?>

]]>
					
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			0