The Date prototype has APIs that allow you to check the year, month, and day-of-month, which seems simple and effective.

You&#39;ll want to decide whether your application needs the dates to be the same from the point of view of the locale where your code runs, or if the comparison should be based on UTC values.

    function sameDay(d1, d2) {
      return d1.getFullYear() === d2.getFullYear() &amp;&amp;
        d1.getMonth() === d2.getMonth() &amp;&amp;
        d1.getDate() === d2.getDate();
    }

There are corresponding UTC getters `getUTCFullYear()`, `getUTCMonth()`, and `getUTCDate()`.


    var isSameDay = (dateToCheck.getDate() === actualDate.getDate() 
         &amp;&amp; dateToCheck.getMonth() === actualDate.getMonth()
         &amp;&amp; dateToCheck.getFullYear() === actualDate.getFullYear())

That will ensure the dates are in the same day.

&gt; Read more about Javascript `Date` [to string][1]


  [1]: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Date/toDateString

I&#39;m trying to overwrite an existing file.
I&#39;m first checking if the file exists using:

    fs.existsSync(path)

If file does not exit I&#39;m creating and writing using:

    fs.writeFileSync(path,string) 

The problem is when the file already exists and I want to over write all its contents.
Is there a single line solution, so far I searched and found solutions that use 
fs.truncate &amp; fs.write, but is there a one hit solution?

What&#39;s the best way to overwrite a file using fs in node.js

I have an array of objects containing some information. I am not able to render them in the order I want and I need some help with that. I render them like this:      

    this.state.data.map(
        (item, i) =&gt; &lt;div key={i}&gt; {item.matchID} {item.timeM} {item.description}&lt;/div&gt;
    )

Is it possible to sort them ascending with `item.timeM` in that `map()`-function or do I have to sort them before i use map? 

Sort an array of objects in React and render them

The JavaScript Date object compare dates with time including, so, if you compare:
`time1.getTime() === time2.getTime()`, they&#39;ll be **&quot;false&quot;** if at least one millisecond is different.

What we need is to have a nice way to compare by Hour, Day, Week, Month, Year?
Some of them are easy, like year: `time1.getYear() === time2.getYear()`
but with day, month, hour it is more complex, as it requires multiple validations or divisions.

Is there any nice module or optimized code for doing those comparisons?

How to tell if two dates are in the same day or in the same hour?

The JavaScript Date object compare dates with time including, so, if you compare:
<code>time1.getTime() === time2.getTime()</code>, they'll be "false" if at least one millisecond is different.
What we need is to have a nice way to compare by Hour, Day, Week, Month, Year?
Some of them are easy, like year: <code>time1.getYear() === time2.getYear()</code>
but with day, month, hour it is more complex, as it requires multiple validations or divisions.
Is there any nice module or optimized code for doing those comparisons?

I&#39;m trying to fetch some data from the REST API of HP Alm. It works pretty well with a small curl script—I get my data.

Now doing that with JavaScript, fetch and ES6 (more or less) seems to be a bigger issue. I keep getting this error message:

&gt; Fetch API cannot load &lt;URL&gt;. Response to preflight request doesn&#39;t
&gt; pass access control check: No &#39;Access-Control-Allow-Origin&#39; header is
&gt; present on the requested resource. Origin &#39;http://127.0.0.1:3000&#39; is
&gt; therefore not allowed access. The response had HTTP status code 501.
&gt; If an opaque response serves your needs, set the request&#39;s mode to
&gt; &#39;no-cors&#39; to fetch the resource with CORS disabled.

I understand that this is because I am trying to fetch that data from within my localhost and the solution should be using [Cross-Origin Resource Sharing (CORS)][1]. I thought I actually did that, but somehow it either ignores what I write in the header or the problem is something else.

So, is there an implementation issue? Am I doing it wrong? I can&#39;t check the server logs unfortunately. I&#39;m really a bit stuck here.

    function performSignIn() {
    
      let headers = new Headers();
    
      headers.append(&#39;Content-Type&#39;, &#39;application/json&#39;);
      headers.append(&#39;Accept&#39;, &#39;application/json&#39;);
    
      headers.append(&#39;Access-Control-Allow-Origin&#39;, &#39;http://localhost:3000&#39;);
      headers.append(&#39;Access-Control-Allow-Credentials&#39;, &#39;true&#39;);
    
      headers.append(&#39;GET&#39;, &#39;POST&#39;, &#39;OPTIONS&#39;);
    
      headers.append(&#39;Authorization&#39;, &#39;Basic &#39; + base64.encode(username + &quot;:&quot; + password));
    
      fetch(sign_in, {
          //mode: &#39;no-cors&#39;,
          credentials: &#39;include&#39;,
          method: &#39;POST&#39;,
          headers: headers
        })
        .then(response =&gt; response.json())
        .then(json =&gt; console.log(json))
        .catch(error =&gt; console.log(&#39;Authorization failed : &#39; + error.message));
    }

I am using Chrome. I also tried using that Chrome CORS Plugin, but then I am getting another error message:

&gt; The value of the &#39;Access-Control-Allow-Origin&#39; header in the response
&gt; must not be the wildcard &#39;*&#39; when the request&#39;s credentials mode is
&gt; &#39;include&#39;. Origin &#39;http://127.0.0.1:3000&#39; is therefore not allowed
&gt; access. The credentials mode of requests initiated by the
&gt; XMLHttpRequest is controlled by the withCredentials attribute.


  [1]: https://developer.mozilla.org/en-US/docs/Web/HTTP/CORS

No &#39;Access-Control-Allow-Origin&#39; header is present on the requested resource—when trying to get data from a REST API

I have a React component and I want to toggle a css class when clicked.

So I have this:


    export class myComponent extends React.Component {
      constructor() {
        super();
        this.state = { clicked: false };
        this.handleClick = this.handleClick.bind(this);
      }
    
      render() {
        return (
          &lt;div&gt;
            &lt;div onClick={this.clicked}&gt;&lt;span ref=&quot;btn&quot; className=&quot;glyphicon&quot;&gt;&amp;nbsp;&lt;/span&gt;&lt;/div&gt;
          &lt;/div&gt;
        );
      }
    
      handleClick() {
        this.refs.btn.classList.toggle(&#39;active&#39;);
      }
    
      componentDidMount() {
        this.refs.btn.addEventListener(&#39;click&#39;, this.handleClick);
        this.setState({
          clicked: this.state.clicked = true,
        });
      }
    
      componentWillUnmount() {
        this.refs.btn.removeEventListener(&#39;click&#39;, this.handleClick);
        this.setState({
          clicked: this.state.clicked = false,
        });
      }
    }

This problem is that ESLint keeps telling me &quot;this.refs&quot; is depreciated.

What do I do instead? How can I fix it so it&#39;s not using depreciated code?


Deprecation warning using this.refs

Say we have a Map: `let m = new Map();`, using `m.values()` returns a map iterator.

But I can&#39;t use `forEach()` or `map()` on that iterator and implementing a while loop on that iterator seems like an anti-pattern since ES6 offer functions like `map()`. 

So is there a way to use `map()` on an iterator?

Using map() on an iterator

I&#39;ve a function like this:

    function top() {
      
      //promise1
      ParentPromise({
        ...some code here...
      }).then(function() {
    
    
        //promise2
            ChildPromise({
              ..some code here...
            }).then(function(response) {
             var result = response.result.items;
             
            });
          
    });
    
    };

and i need to return result value in this way:

    var myresult = start();
How i can do that? THX

Promise inside promise: what&#39;s the correct way to return a variable from the child promise? (JS)

It&#39;s my understanding that these two functions will have the same behavior in JavaScript:

    const whatever1 = (): Promise&lt;number&gt; =&gt; {
        return new Promise((resolve) =&gt; {
            resolve(4);
        });
    };

    const whatever2 = async (): Promise&lt;number&gt; =&gt; {
        return new Promise((resolve) =&gt; {
            resolve(4);
        });
    };

But TypeScript seems to not like the second one, it says:

    Type &#39;{}&#39; is not assignable to type &#39;number&#39;.

Is this a bug in TypeScript, or am I misunderstanding something about async functions?

Returning a promise in an async function in TypeScript

I&#39;m trying to make a cast in my code from the body of a request in express (using body-parser middleware) to an interface, but it&#39;s not enforcing type safety.

This is my interface:

    export interface IToDoDto {
      description: string;
      status: boolean;
    };

This is the code where I&#39;m trying to do the cast:

    @Post()
    addToDo(@Response() res, @Request() req) {
      const toDo: IToDoDto = &lt;IToDoDto&gt; req.body; // &lt;&lt;&lt; cast here
      this.toDoService.addToDo(toDo);
      return res.status(HttpStatus.CREATED).end();
    }

And finally, the service method that&#39;s being called:

    public addToDo(toDo: IToDoDto): void {
      toDo.id = this.idCounter;
      this.todos.push(toDo);
      this.idCounter++;
    }

**I can pass whatever arguments, *even ones that don&#39;t come close to matching the interface definition*, and this code will work fine.** I would expect, if the cast from response body to interface is not possible, that an exception would be thrown at runtime like Java or C#.

I have read that in TypeScript casting doesn&#39;t exist, only Type Assertion, so it will only tell the compiler that an object is of type `x`, so... Am I wrong? What&#39;s the right way to enforce and ensure type safety? 

Cast object to interface in TypeScript

I&#39;ve a lot of tables in [Lovefield][1] and their respective Interfaces for what columns they have.

Example:

&lt;!-- language: lang-ts --&gt;

    export interface IMyTable {
      id: number;
      title: string;
      createdAt: Date;
      isDeleted: boolean;
    }

I&#39;d like to have the property names of this interface in an array like this:

&lt;!-- language: lang-ts --&gt;

    const IMyTable = [&quot;id&quot;, &quot;title&quot;, &quot;createdAt&quot;, &quot;isDeleted&quot;];


I cannot make an object/array based on the interface `IMyTable` directly which should do the trick because I&#39;d be getting the interface names of the tables dynamically. Hence I need to iterate over these properties in the interface and get an array out of it.

How do I achieve this result?


  [1]: https://github.com/google/lovefield


Get keys of a Typescript interface as array of strings

I am new in Angular2. I have tried to create a component but showing an error.

This is the `app.component.ts` file.

    import { Component } from &#39;@angular/core&#39;;
    import { MyComponentComponent } from &#39;./my-component.component&#39;;
 
    @Component({
      selector: &#39;my-app&#39;,
      template: `
        &lt;h1&gt;Hello {{name}}&lt;/h1&gt;
        &lt;h4&gt;Something&lt;/h4&gt;
        &lt;my-component&gt;&lt;/my-component&gt;
      `,
      directives: [MyComponentComponent]
    })
    export class AppComponent { name = &#39;Sam&#39; }

This is the component which i want to create.


    import { Component } from &#39;@angular/core&#39;;

    @Component({
    selector: &#39;my-component&#39;,
    template: `
        &lt;p&gt;This is my article&lt;/p&gt;
    `
    })

    export class MyComponentComponent {

    }

Showing the two errors:

1. If `my-component` is an Angular component, then verify that it is part of this module.
2. If `my-component` is a Web Component then add `CUSTOM_ELEMENTS_SCHEMA` to the `@NgModule.schemas` of this component to suppress this message. 

Please Help.

If &#39;&lt;selector&gt;&#39; is an Angular component, then verify that it is part of this module

I want to be able to scroll to a target when a button is pressed. I was thinking something like this.

    &lt;button (click)=&quot;scroll(#target)&quot;&gt;Button&lt;/button&gt;

And in my `component.ts` a method like.

    scroll(element) {
        window.scrollTo(element.yPosition)
    }

I know that the code above is not valid but just to show what I was thinking. I&#39;ve just started to learn Angular 4 with no previous experience of Angular. I&#39;ve been searching around for something like this but all the examples are in AngularJs which differs alot to Angular 4
   

Content Type	Original Author	Original Content on Stackoverflow
Question	reza	View Question on Stackoverflow
Solution 1 - Javascript	Pointy	View Answer on Stackoverflow
Solution 2 - Javascript	Daniel Taub	View Answer on Stackoverflow

How to tell if two dates are in the same day or in the same hour?

Javascript Problem Overview

Javascript Solutions

Solution 1 - Javascript

Solution 2 - Javascript

Sort an array of objects in React and render them

What's the best way to overwrite a file using fs in node.js

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