how to use the bindall function from the underscore library in javascript

The bindAll function from the Underscore.js library allows you to bind the this context of multiple methods in an object to that object. This can be useful, for example, when working with event handlers that need to reference the associated object instance.

Here is an example of how to use bindAll:

index.tsx
const obj = {
  name: 'example',
  logName: function() {
    console.log(this.name);
  },
  logFoo: function() {
    console.log('foo');
  }
};

// Before bindAll
obj.logName(); // "example"
const logName = obj.logName;
logName(); // Throws an error: `this` is undefined

// After bindAll
_.bindAll(obj, 'logName', 'logFoo');
obj.logName(); // "example"
const logName = obj.logName;
logName(); // "example"
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In this example, we create an object with two methods, logName and logFoo. We then bind these methods using bindAll. This allows us to use the methods without worrying about the this context.

Note that we pass the method names as additional arguments to bindAll. If we had many methods to bind, we could pass them as an array instead.

index.tsx
_.bindAll(obj, ['logName', 'logFoo']);
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Also note that bindAll modifies the original object, so use it carefully.