How to call method recursively in typescript

Question

I want to call the filterArr inside the filterArr. Here is my implementation.

 filterArr(array, search) {
        var result = [];
        array.forEach((a)=> {
            var temp = [],
                 o = {},
                found = false;

            if (a.name === search) {
                this.o.name = a.name;
                found = true;
            }
            if (Array.isArray(a.children)) {
                temp = this.filterArr(a.children, search);//***Cannot read property 'filterArr' of undefined***
                if (temp.length) {
                    this.o.children = temp;
                    found = true;
                }
            }
            if (found) {
                result.push(o);
            }
        });
        return result;
    }

How to call the filterArr method without any error?

Does it show any warning if you remove the `this.` part of `this.filterArr(a.children, search)`? — Washington Guedes, Jun 21 '17 at 10:17
Possible duplicate of [How to access the correct \`this\` context inside a callback?](https://stackoverflow.com/questions/20279484/how-to-access-the-correct-this-context-inside-a-callback) — eko, Jun 21 '17 at 10:19

score 3 · Accepted Answer · answered Jun 21 '17 at 10:18

3

You have to use Arrow function to get hold on correct this, so you need to change array.forEach(function (a) { to use `Arrow function

array.forEach((a) => {

answered Jun 21 '17 at 10:18

Pankaj Parkar

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How to call method recursively in typescript

1 Answers1