You can use typeof operator: Example from this webpage. (Example was slightly modified though). This won’t work as expected in the case of strings created with new String(), but this is seldom used and recommended against[1][2]. See the other answers for how to handle these, if you so desire. The Google JavaScript Style Guide says to never use primitive object … Read more
My solution breaks down in 3 parts: the state of the user is stored in a service, in the run method you watch when the route changes and you check if the user is allowed to access the requested page, in your main controller you watch if the state of the user change. You should … Read more
I have this error when I compile my code in node.js, how can I fix it? RefernceError: fetch is not defined This is the function I am doing, it is responsible for recovering information from a specific movie database.
JSON itself does not specify how dates should be represented, but JavaScript does. You should use the format emitted by Date‘s toJSON method: 2012-04-23T18:25:43.511Z Here’s why: It’s human readable but also succinct It sorts correctly It includes fractional seconds, which can help re-establish chronology It conforms to ISO 8601 ISO 8601 has been well-established internationally for more than a decade ISO 8601 is endorsed … Read more
I am trying to set up my React.js app so that it only renders if a variable I have set is true. The way my render function is set up looks like: Basically, the important portion here is the if(this.state.submitted==false) portion (I want these div elements to show up when the submitted variable is set to false). But when running this, I get … Read more
For some number y and some divisor x compute the quotient (quotient) and remainder (remainder) as:
Here is the code
This works in all browsers: If you wanted to change the page without it reflecting in the browser back history, you can do:
An “undefined variable” is different from the value undefined. An undefined variable: A variable with the value undefined: When a function takes an argument, that argument is always declared even if its value is undefined, and so there won’t be any error. You are right about != null followed by !== undefined being useless, though.
It’s document.getElementById, not document.getElementbyId. (In JS, name of variables and functions are case-sensitive) Debugging tip : Look at the JS console (F12 in Google Chrome and IE9, Ctrl+Shift+K in Firefox). In this case, following error can be seen: It shows where the error happened (line 260 in your HTML/JS code) and what the error is(Object #<HTMLDocument> has no method getElementbyId).