Pen Settings

HTML

CSS

CSS Base

Vendor Prefixing

Add External Stylesheets/Pens

Any URL's added here will be added as <link>s in order, and before the CSS in the editor. If you link to another Pen, it will include the CSS from that Pen. If the preprocessor matches, it will attempt to combine them before processing.

+ add another resource

JavaScript

Babel is required to process package imports. If you need a different preprocessor remove all packages first.

Add External Scripts/Pens

Any URL's added here will be added as <script>s in order, and run before the JavaScript in the editor. You can use the URL of any other Pen and it will include the JavaScript from that Pen.

+ add another resource

Behavior

Save Automatically?

If active, Pens will autosave every 30 seconds after being saved once.

Auto-Updating Preview

If enabled, the preview panel updates automatically as you code. If disabled, use the "Run" button to update.

Format on Save

If enabled, your code will be formatted when you actively save your Pen. Note: your code becomes un-folded during formatting.

Editor Settings

Code Indentation

Want to change your Syntax Highlighting theme, Fonts and more?

Visit your global Editor Settings.

HTML

              
                <textarea id='cont'></textarea>
	<p><input type="button" value="匹配进行时的单词" onclick="t1();"></p>
	<p><input type="button" value="匹配进行时的单词的词根部分,正向预查" onclick="t2();"></p>
	<p><input type="button" value="查找winxp,负向预查" onclick="t3();"></p>
	<p><input type="button" value="找出un*系列单词的词根" onclick="t4();"></p>
              
            
!

CSS

              
                		textarea{
			width: 400px;
			height: 200px; 
		}
              
            
!

JS

              
                function t1(){
  var cont = document.getElementById('cont');
  var cv = cont.value;
  var reg = /\b[\w]+ing\b/;
  alert(cv.match(reg));
} 
function t2(){
  var cont = document.getElementById('cont');
  var cv = cont.value;
  var reg = /\b[\w]+(?=ing)/g;//匹配进行时的单词的词根部分  不要ing结尾  预查不消耗字符
  alert(cv.match(reg));
} 
function t3(){
  var cont = document.getElementById('cont');
  var cv = cont.value;
  var reg = /\bwin(?!95)/g;//win98 win97 win95 win32 winxp win2003要求把win95过滤
  alert(cv.match(reg));
} 
function t4(){
  var cont = document.getElementById('cont');
  var cv = cont.value;
  //var reg = /\w+(?<=un)/g;//找出un*系列单词的词根  js不支持向前正向预查
  alert(cv.match(reg));
} 
              
            
!
999px

Console