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<returns> (JavaScript)

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Note

This article applies to Visual Studio 2015. If you're looking for the latest Visual Studio documentation, see Visual Studio documentation. We recommend upgrading to the latest version of Visual Studio. Download it here

Specifies documentation information for the result of a function or method call.

Syntax

<returns type="ValueType" integer="true|false"
    domElement="true|false" mayBeNull="true|false"
    elementType="ArrayElementType" elementInteger="true|false"
    elementDomElement="true|false" elementMayBeNull="true|false"
    locid="descriptionID" value="code">description
</returns>

Parameters

type Optional. The data type of the return value. The type can be one of the following:

  • An ECMAScript language type in the ECMAScript 5 specification, such as Number and Object.

  • A DOM object, such as HTMLElement, Window, and Document.

  • A JavaScript constructor function.

    integer Optional. If type is Number, specifies whether the return value is an integer. Set to true to indicate that the return value is an integer; otherwise, set to false. This attribute is not used by Visual Studio to provide IntelliSense information.

    domElement Optional. This attribute is deprecated; the type attribute takes precedence over this attribute. This attribute specifies whether the documented return value is a DOM element. Set to true to specify that the return value is a DOM element; otherwise, set to false. If the type attribute is not set and domElement is set to true, IntelliSense treats the documented return value as an HTMLElement when performing statement completion.

    mayBeNull Optional. Specifies whether the documented return value can be set to null. Set to true to indicate that the return value can be set to null; otherwise, set to false. The default value is false. This attribute is not used by Visual Studio to provide IntelliSense information.

    elementType Optional. If type is Array, this attribute specifies the type of the elements in the array.

    elementInteger Optional. If type is Array and elementType is Number, this attribute specifies whether the elements in the array are integers. Set to true to indicate that the elements in the array are integers; otherwise, set to false. This attribute is not used by Visual Studio to provide IntelliSense information.

    elementDomElement Optional. This attribute is deprecated; the elementType attribute takes precedence over this attribute. If type is Array, this attribute specifies whether the elements in the array are DOM elements. Set to true to specify that the elements are DOM elements; otherwise, set to false. If the elementType attribute is not set and elementDomElement is set to true, IntelliSense treats each element in the array as an HTMLElement when performing statement completion.

    elementMayBeNull Optional. If type is Array, specifies whether the elements in the array can be set to null. Set to true to indicate that the elements in the array can be set to null; otherwise, set to false. The default value is false. This attribute is not used by Visual Studio to provide IntelliSense information.

    locid Optional. The identifier for localization information about the return value. The identifier is either a member ID or it corresponds to the name attribute value in a message bundle defined by OpenAjax metadata. The identifier type depends on the format specified in the <loc> tag.

    value Optional. Specifies code that should be evaluated for use by IntelliSense instead of the function code itself. For example, you can use this attribute to provide IntelliSense for asynchronous callbacks, such as a Promise. Using the value attribute with the <returns> element can improve IntelliSense performance by bypassing lengthy code execution.

    description Optional. A description of the return value.

Remarks

The <returns> element must be placed in the function body before any statements.

Example

The following code example shows how to use the <returns> element.

function areaFunction(radiusParam)
{
    /// <summary>Determines the area of a circle when provided a radius parameter.</summary>
    /// <param name="radiusParam" type="Number">The radius of the circle.</param>
    /// <returns type="Number">The area.</returns>
    var areaVal;
    areaVal = Math.PI * radiusParam * radiusParam;
    return areaVal;
}

// The following examples use the <remarks> element with a value attribute.

function getJson(complete) {
    /// <returns value='complete("")' ></returns>
    var r = new XMLHttpRequest();
    // . . .
}

getJson(function (json) {
    json.  // IntelliSense for a String object is
           // available here.
});

function calculate(x) {
    /// <returns value='1'/>
}
calculate().  // Completion list for a Number.

See Also

XML Documentation Comments