ko.utils.arrayFirst = function（array，predicate，predicateOwner）{/ * .. * /}

Question

predicateOwner是什麼意思，我找不到答案？

這樣的：

How to use indexOf in KnockoutJS

或

https://gist.github.com/hyle/8840a083bcd1325a59ca

Answer 1

arrayFirst的最新參數 - 是將分配給謂詞的範圍方面：

var array = ko.observableArray([1,2,3]); 
 
var context = "Hello"; 
 
var result = ko.utils.arrayFirst(array(), function(item) { 
 
    // 'this' is equal 'context' 
 
    console.log(this); 
 
    return item === 2; 
 
}, context);

<script src="https://cdnjs.cloudflare.com/ajax/libs/knockout/3.4.2/knockout-min.js"></script>