Question

I am creating an attribute in a javascript object by replacing some strings in an existing object, as a side effect I want to make some additional changes to a third property, which I try to access with this.property however in the replace function this is referring to the window instead of my ‘master’ object. How can I pass in the encapsulating object, so that I can use this to access third property.

b = {
    a: 'onetwothree',
    count: 0,
    rp: function () {
        this.c = this.a.replace(/e/g, function (str, evalstr) {
            this.count++; // <-- this is refering to window.
            return 'e' + this.count
        })
    }
};
b.rp();

b.c = 'oneNaNtwothreNaNeNaN whereas I want it to be one1twothre2e3

Answer 1

rp: function () {
    this.c = this.a.replace(/e/g, function (str, evalstr) {
        this.count++;
        return 'e' + this.count
    }.bind( this )) // <-- bind the function
}