javascript - Why should "this" be assigned to variable in jQuery? -

-

In some jQuery code I often think that this is assigned to the variable in jQuery and I do not understand the reason for this approach?

This is an example of a jQuery plugin builder: 

  // constructor function Nullpoll (element, option) {var widget = this; Widget.config = $ .extend ({}, default, options); Widget.element = element; Widget.element.on ("click", function () {alert ("test")}; Widget.element.one ("change", function (e) {widget.element.find ("button"). RemoveProp ("disabled");}); This.init (); }

The value of this is determined by how <

  1. or
  2. (more commonly) to give it a more informative name so that value one different Function , which can reach the scope of the first function

In this particular case, widget.element.one () Near anonymously function call this call to call Nullpoll . If it tries to use the this keyword, then it will get a different value (how the value depends on whether a a function is called a mismatch function) < / P>


Comments

Post a Comment

Popular posts from this blog

java - Can't add JTree to JPanel of a JInternalFrame -

-
Image
There are two panels in my JInternalframe. I want to add TopPanel to Jtree to nominate another. But I can not add Jaitari to the top of the panel. Please help me in this piece of code: DefaultMutableTreeNode root = new DefaultMutableTreeNode ("deck"); DefaultMutableTreeNode Item Clubs = New DefaultMutableTreeNode ("Club"); AddAllCard (itemClubs); Root.add (itemClubs); DefaultMutableTreeNode item = New DefaultMutableTreeNode ("Diamonds"); AddAllCard (itemDiamonds); Root.add (itemDiamonds); DefaultMutableTreeNode Itemspads = New DefaultMutableTreeNode ("Spades"); AddAllCard (itemSpades); Root.add (itemSpades); DefaultMutableTreeNode item increases = new DefaultMutableTreeNode ("heart"); AddAllCard (itemHearts); Root.add (itemHearts); Default Trimodel Tree Model = New DefaultTreeModel (Route); Tree = new jetty (tree modal); ScrollPane = new JScrollPane (tree); // scrollPane.setViewportView (tree); . ScrollPane.getViewport () add (tr
Read more

javascript - data.match(var) not working it seems -

-
OK, I have this small block code, which is to scanned a number on the website, but for some reason There is a hip that it is not scanning at all. var regenges = / \ & lt; Span class = "currency-robux" data-to-"item-private-value-price" & gt; ([\ D,]) \ & LT; \ / Span \ & gt; /; Var ValueCiling = Data. Match (reggae); Value-song = number (value slicing location (",", "")); Is there anything wrong with that? This is related to the if statement if (value sling and lieutenant; = price watching) { < P> A function calls to move from there, but for some reason it does not seem to run at all. So I think the Regex is wrong but I'm not sure how. (There is a variable in PriceWinking , this is a snippet from the code.) On the website, I'm trying to remove it. & lt; Span class = "robux" data-plus = "item-privatesale-price" & gt; 115 & lt; / Span & gt; Keep in mind
Read more

javascript - How can I pause a jQuery .each() loop, while waiting for user input? -

-
Before I continue to get a jQuery .each loop to wait for user input There is a problem in repeatedly repeating This is my code (I have commented on what I would like to do): & lt; Html xmlns = "http://www.w3.org/1999/xhtml" & gt; & Lt; Top & gt; & Lt; Link rel = "stylesheet" type = "text / css" href = "common_components.css" /> & Lt; Meta http-equiv = "content-type" content = "text / html; charset = UTF-8" /> & Lt; Link rel = "stylesheet" href = "slider.css" & gt; & Lt ;? Php include_once 'common_components.php'; $ Query = $ dbh- & gt; Queries ("SELECT movies_dir FROM settings"); $ Line = $ query- & gt; Obtain (PDO :: FETCH_ASSOC); Date_default_timezone_set ('UTC'); Echo "& lt; title & gt; movie scanner & lt; / title & gt;"; ? & Gt; & Lt; Script src = "jquery.min.js" & gt; &am
Read more