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KnockoutJS - indexOf() Method
Description
The KnockoutJS Observable indexOf('value') method returns the index of the first occurrence of the parameter provided. This function will return -1, if no matching element is found.
Syntax
arrayName.indexOf('value')
Parameters
Accepts 1 parameter, whose index will be returned.
Example
<!DOCTYPE html>
<head>
<title>KnockoutJS ObservableArray indexOf method</title>
<script src = "https://ajax.aspnetcdn.com/ajax/knockout/knockout-3.1.0.js"
type = "text/javascript"></script>
</head>
<body>
<p>Example to demonstrate indexOf() method.</p>
<p>Index of Employee 'Jordan':
<span data-bind = "text: empArray().indexOf('Jordan')"></span>
</p>
<p>Array of employees: <span data-bind = "text: empArray()" ></span></p>
<script>
function EmployeeModel() {
this.empName = ko.observable("");
this.chosenItem = ko.observableArray("");
this.empArray = ko.observableArray(['Scott','James','Jordan','Lee',
'RoseMary','Kathie']);
}
var em = new EmployeeModel();
ko.applyBindings(em);
</script>
</body>
</html>
Output
Let's carry out the following steps to see how the above code works −
Save the above code in array-indexof.htm file.
Open this HTML file in a browser.
knockoutjs_observables.htm
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