During the interview, I was asked such a question: "1" = 1, what are the rules for data type conversion, and how to judge?

the question "1" = = 1 is asked during the interview, and this judgment condition will convert "1" to number type 1 when executed, but how to verify it? (do I want to pass code verification? Because I don"t know how to verify it, I game over). Once again, my IQ has been crushed.

if it is an object and {} = = 1, the object is converted to the original value, which can be verified by the valueOf method that defines the object, 

{valueOf:()=>{console.log("test")}} ==1;

but as mentioned in the title, how do you verify that a string is converted to a number?

Node.js javascript
Mar.16,2022

either the string from 1 to "1" or the number from "1" to 1

verify "1.00000" = = 1 

Number.prototype.toString = function (v) {
  console.log('number');
  return v;
}

String.prototype.valueOf = function (v) {
  console.log('string');
  return '1';
}

1, object and undefined are compared by pointer
2, other types and numbers can be compared like this:'1' = = 1 = > Number ('1') = Number (1)

Previous: Is the vue skeleton screen used with ssr? After using vue-Skeleton, start the project and report the error of window is not defined

Next: The problem that vue axios requests parameters to carry an array of objects to ssm

css mysql arrays josn react html typescript webpack npm sass R objective-c .net sql-server jquery python-3.x angularjs django angular excel regex iphone ajax linux xml pandas vba spring database wordpress string wpf xcode windows bash postgresql oracle multithreading eclipse list firebase algorithm macos forms image scala visual-studio azure bootstrap spring-boot react-native python-2.7 docker performance function winforms matlab powershell apache dataframe api sqlite numpy rest shell selenium flutter dart maven loops qt swing android-studio csv express file class tensorflow sorting codeigniter perl
© 2021 CodesHelper
Advertising Contact us About us
Menu