Solve the thirdscripterror error of wechat applet

Recently, I got into the pit of wechat applet , A lot of problems , Today's question is  thirdScriptError！

The error message is as follows ：

Wrong version source code （ Code unrelated to this error has been deleted ）：

Page({
  data: {
    // Used to hold input Input content of 
    words:null
  },


  // obtain input Content of input box 
  input:function(e){
    this.setData({words:e.detail.value})
  },
 
  // Click button , Print out the contents of the input box in the log 
  btnclick:function(){
    console.log(words)
  }
})

Correct source code ：

Page({
  data: {
    words:null
  },

  input:function(e){
    this.setData({words:e.detail.value})
  },
 
  btnclick:function(){
    // Not directly through words visit ！！！！！！！！！
    console.log(this.data.words)
  },
})

The reason for the error ：

Referencing variables in functions requires this Point to ！！！

For the first time ：

I encountered this mistake again , The reason this time is very retarded , Is in the js When assigning values to variables in the file, you should use colons , I accidentally used the equal sign .

error ：

myData: {
    username="hello"
}

correct ：

myData: {
    username:"hello"
}