唐霜的博客

In many react component's constructor, developers always bind its methods with this, like:

export default class MyComponent extends Component {
  constructor() {
    this.say = this.say.bind(this)
  }
  ...
}

This sentence seems to be stupid. Is this regulated by react?

No!

In fact, react component class follow ES6 class std. The reason to put this sentence is because when you use this.say in your render, you alway use it as onClick callback function, this is why this is not point to instance of this component. Let's look into this code:

<a href="" onclick="alert(this.href)">click</a>

You know what this point to here, so when you use a component method as a event callback function, this in the function does not referer to the instance of component. So another way to solve this problem is to bind this when you use the method, like:

export default class MyComponent extends Component {
  constructor() {
    // do not use bind sentence
  }
  render() {
    return <a onClick={this.say.bind(this)}>click</a>
  }
}

Now you can use this in say as want you want.

When I downloaded the free old version of Adobe Photoshop CS2 and installed it on windows10, I found it is not able to launch the software, it comes out with a error alert, and force me to close the program. I was aware of it is a compatibility problem, but not know how to fix it. After tried a lot, I found the most easy way: using windows application tools.

1. close your photoshop cs2 alert first
2. open your photoshop cs2 installed directory, and select Photoshop.exe
3. on the top of the screen, there will be a tab named Manage
4. click Troubleshoot compatibility item
5. follow what it call you to do, try more
6. done

And you may need to run photoshop as administrator, for this, right click on Photoshop.exe and open properties, change to Compatibility to select Run this program as an administrator.