School Website Templates Html With Css Jquery Padding
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AJAX ed Todo List With PHP, My. SQL j. Query. In this tutorial we are making a simple AJAX ed Todo List App, with PHP, My. SQL and j. Query. In the process we are going to demonstrate PHPs OOP capabilities, play with j. Query UI and implement some nice AJAX functionality. Note This tutorial is quite old and doesnt work in PHP7 and above. We are keeping it online only as a reference. For a better understanding of the steps of this tutorial, you an go ahead and download the demo archive available from the button above. Step 1 PHPAs this is more of a developer oriented tutorial, we are going to start with the PHP part. Unlike previous tutorials, this time we are leveraging the OOP features of PHP 5. If youre heading back to school, theres no doubt youve got a long list of required reading material. Whether its a classic like The Great Gatsby, or a. In this tutorial we are making a simple AJAXed Todo List App, with PHP, MySQL and jQuery. In the process we are going to demonstrate PHPs OOP capabilities, play. The author presumes you have a basic understanding of the core concepts behind object oriented programming, and PHP 5s OOP implementation. For a quick reference, check out these pages of PHPs documentation OOP Basics, Static Methods, Exceptions, Magic Methods. All of the functionality available to the end user creating, editing, deleting and reordering the todo items is implemented as different methods of a class, explained in detail below. Climate change is scary, especially when stories about our planets dire future come handinhand with news about what our federal government isnt going to do. Part 1 Defining the To. Do class. An array that stores the todo item data. The constructor. This is an in build magic method that is automatically called. PHP when we output the To. School Website Templates Html With Css Jquery Padding' title='School Website Templates Html With Css Jquery Padding' />Do objects with echo. String. The string we return is outputted by the echo statement. Editlt a. lt a href classdelete Deletelt a. The constructor takes the array passed as a parameter and stores it in the data property of the class. This array is a row fetched from the database with mysqlfetchassoc and contains the id and the text of the todo item. Free Roblox Hacking Free Programs. After this is the magic to. String method, which is called internally when we attempt to echo out an object of this class. The string it returns contains the markup used by each todo item a lt li element with a unique id and a classname todo, inside of which we have the text of the todo and the two action hyperlinks. Part 2 The edit method takes the To. Do item id and the new text. To. Do. Updates the database. ExceptionWrong update text. UPDATE tztodo. SET text. WHERE id. id. GLOBALSlink1. ExceptionCouldnt update item. The delete method. Takes the id of the To. Do item. and deletes it from the database. DELETE FROM tztodo WHERE id. GLOBALSlink1. ExceptionCouldnt delete item. The rearrange method is called when the ordering of. Takes an array parameter, which. Vals array. foreachkeyvalue as k v. Vals WHEN. intv. THEN. PHPEOL. ifstr. Vals throw new ExceptionNo data. We are using the CASE SQL operator to update the To. Do positions en masse. UPDATE tztodo SET position CASE id. Vals. ELSE position. END. ifmysqlerrorGLOBALSlink. ExceptionError updating positions. The definition of the class continues with a number of static methods. Those are special methods, which can be accessed without the need of an object of the class to be created. For example, you can call the edit method by writing To. Do editpar. 1,par. Notice how we are using exceptions to handle errors. When an exception occurs the script execution halts and it is up to the rest of the script to catch it and output the appropriate status. Also you may find interesting the way we are updating the database with the new positions of the todo items. We are using the CASE operator, available in My. SQL. This way, no matter how many todos are in the database, we execute only one query. Saving queries and optimizing your scripts, although tedious, is hugely beneficial in the long run. You can read more about the CASE operator among other interesting features in My. SQLs official documentation. Part 3 The create. New method takes only the text of the todo as a parameter. AJAX front end. public static function create. Newtext. text self esctext. ExceptionWrong input data. Result mysqlquerySELECT MAXposition1 FROM tztodo. Result. listposition mysqlfetcharraypos. Result. ifposition position 1. INSERT INTO tztodo SET text. GLOBALSlink1. ExceptionError inserting TODO. Creating a new To. Do and outputting it directly. To. Doarray. id mysqlinsertidGLOBALSlink. A helper method to sanitize a string. Accessing static methods from the same class can easily be done with the self keyword. This way we are using the esc method to sanitize the incoming user data. Also notice the create. New method. In it, after running the INSERT query on the database, we use the returned auto assigned unique id with mysqlinsertid and create a new todo object, which is then echoed out to the front end. Now lets take a look at how this class is used. Part 1 Select all the todos, ordered by position. Zerif Pro on this page. SELECT FROM tztodo ORDER BY position ASC. Filling the todos array with new To. Do objects. whilerow mysqlfetchassocquery. To. Dorow. After including todo. My. SQL result set, filling in the todos array with objects. Part 2 Looping and outputting the todos array. The to. String method. Later in the page, these objects are echoed out. Thanks to the to. String method discussed above, all the markup is automatically generated, so we do not have to deal with any of that. The front end issues a number of different AJAX calls. Making a separate file to handle each of them would be a bit of overkill, so the best solution is to group them in a single AJAX handling file. This is done in ajax. GETid. switchGETaction. To. Do deleteid. To. Do rearrangeGETpositions. To. Do editid,GETtext. To. Do create. NewGETtext. Exception e. echo e get. Message. echo 1 With the help of a switch statement, we decide which of the static methods of the To. Do class to execute. If an error occurs in one of these methods, an exception is dispatched. Because the whole switch is enclosed in a try statement, execution of the script halts and control is passed to the catch statement, which outputs a zero and exits the script. You could potentially echo or write to a log exactly what kind of error occurred by uncommenting line 2. Step 2 My. SQLThe tztodo table holds and assigns the unique ids of the todo items via the autoincrement setting of the field, the position, the text and the dtadded timestamp. You can find the SQL that will recreate the table in table. Also, if you plan to run the demo on your own server, dont forget to fill in your login details in connect. Step 3 XHTMLAs most of the markup is generated by PHP, we are left with taking care of the rest of the pages XHTML. First we need to include j. Query, j. Query UI, and the stylesheets in the document. It is considered a good practice to include the stylesheets to the head section, and the Java. Script files right before the closing lt body tag. After this we can move on to coding the rest of the page. List. Looping and outputting the todos array. The to. String method. Button classgreen button href Add a To. Dolt a. lt This div is used as the base for the confirmation j. Query UI dialog box.