getelementbyid

问题 All browsers I\'ve come to work with allow accessing an element with id=\"myDiv\" by simply writing: myDiv See here: http://jsfiddle.net/L91q54Lt/ Anyway, this method seems to be quite poorly documented, and in fact, the sources I come across don\'t even give it a mention and instead assume that one would use document.getElementById(\"myDiv\") or maybe document.querySelector(\"#myDiv\") to access a DOM element even when its ID is known in advance (i.e. not calculated at runtime). I can tell

问题 When should you use document.all vs. document.getElementById ? 回答1: document.all is a proprietary Microsoft extension to the W3C standard. getElementById() is standard - use that. However, consider if using a js library like jQuery would come in handy. For example, $("#id") is the jQuery equivalent for getElementById() . Plus, you can use more than just CSS3 selectors. 回答2: document.all is very old, you don't have to use it anymore. To quote Nicholas Zakas: For instance, when the DOM was

问题 How do I select certain bars in react.js? This is my code: var Progressbar = React.createClass({ getInitialState: function () { return { completed: this.props.completed }; }, addPrecent: function (value) { this.props.completed += value; this.setState({ completed: this.props.completed }); }, render: function () { var completed = this.props.completed; if (completed < 0) { completed = 0 }; return (...); } I want to use this React component: var App = React.createClass({ getInitialState: function

问题 I\'m trying to toggle the visibility of certain DIV elements on a website depending on the class of each DIV. I\'m using a basic JavaScript snippet to toggle them. The problem is that the script only uses getElementById , as getElementByClass is not supported in JavaScript. And unfortunately I do have to use class and not id to name the DIVs because the DIV names are dynamically generated by my XSLT stylesheet using certain category names. I know that certain browsers now support

问题 Working on an idea for a simple HTMLElement wrapper I stumbled upon the following for Internet Explorer and Chrome: For a given HTMLElement with ID in the DOM tree, it is possible to retrieve the div using its ID as the variable name. So for a div like <div id=\"example\">some text</div> in Internet Explorer 8 and Chrome you can do: alert(example.innerHTML); //=> \'some text\' or alert(window[\'example\'].innerHTML); //=> \'some text\' So, does this mean every element in the DOM tree is