The void operator evaluates the given expression and then returns undefined. The void operator is often used merely to obtain the undefined primitive value, usually using “void(0)” (which is equivalent to “void 0”). In these cases, the global variable undefined can be used instead (assuming it has not been assigned to a non-default value). An explanation is provided here: void operator. The reason you’d want to … Read more
stopPropagation prevents further propagation of the current event in the capturing and bubbling phases. preventDefault prevents the default action the browser makes on that event. Examples preventDefault stopPropagation With stopPropagation, only the button‘s click handler is called while the div‘s click handler never fires. Where as if you use preventDefault, only the browser’s default action is stopped but the div’s click handler still … Read more
Here’s a sample on how to use CryptoJs in webclient:
There are some examples on the Mozilla Developer Network page: Here’s the logic behind it. It’s a simple rule of three: Math.random() returns a Number between 0 (inclusive) and 1 (exclusive). So we have an interval like this: Now, we’d like a number between min (inclusive) and max (exclusive): We can use the Math.random to get the correspondent in the [min, max) interval. But, first we … Read more
Dev Tools remembers the last five DOM elements (or JavaScript heap objects) that you’ve selected in the tab (or Profiles panel). It makes those objects available as $0, $1, $2, $3, and $4. $0 returns the most recently selected element or JavaScript object, $1 returns the second most recently selected one, and so on. See this for more information.
Ways to clear an existing array A: Method 1 (this was my original answer to the question) This code will set the variable A to a new empty array. This is perfect if you don’t have references to the original array A anywhere else because this actually creates a brand new (empty) array. You should be careful with this method because … Read more
You are calling ReactDOM.render within a React component that doesn’t get rendered. Call ReactDOM render outside of the class definition for help To render your button to the screen: That’s it. To avoid confusion should try and give your components meaningful names. Naming both of them Help can get confusing when you are trying to import one … Read more
Use location.reload(): The reload() function takes an optional parameter that can be set to true to force a reload from the server rather than the cache. The parameter defaults to false, so by default the page may reload from the browser’s cache.
Check out the built-in function encodeURIComponent(str) and encodeURI(str).In your case, this should work:
To do this for any object in JavaScript will not be simple or straightforward. You will run into the problem of erroneously picking up attributes from the object’s prototype that should be left in the prototype and not copied to the new instance. If, for instance, you are adding a clone method to Object.prototype, as some answers depict, … Read more