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Type.inheritsFrom Method

  • Article

Determines whether an instance inherits from a specified class.

var isInheritedFromVar = TypeA.inheritsFrom(parentType);

Parameters

  • parentType
    The fully qualified name of the class to test as a base class for the current instance.

Return Value

true if the instance inherits from parentType; otherwise, false.

Remarks

Use the inheritsFrom method to determine whether a type inherits from a specific base type.

Example

The following example shows how to use the inheritsFrom method to determine whether one class inherits from another class.

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "https://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">

<html xmlns="https://www.w3.org/1999/xhtml" >
<head id="Head1" runat="server">
    <title>Sample</title>
</head>
<body>
    <form id="form1" runat="server">
       <asp:ScriptManager runat="server" ID="ScriptManager1">
       </asp:ScriptManager>

       <script type="text/javascript">
        // Register classes to test.
        Type.registerNamespace('Samples');

        Samples.A = function()
        {
            // Initialize as a base class.
            Samples.A.initializeBase(this);
        }

        Samples.B = function(){}
        Samples.C = function(){}

        Samples.A.registerClass('Samples.A');
        Samples.B.registerClass('Samples.B', Samples.A);

        Samples.C.registerClass('Samples.C');

        var isDerived;
        isDerived = Samples.B.inheritsFrom(Samples.A);
        // Output: "true".
        alert(isDerived);

        isDerived = Samples.C.inheritsFrom(Samples.A);
        // Output: "false".
        alert(isDerived);

        </script>
    </form>

</body>
</html>

See Also

Reference

Type Class