# apex:param

A parameter for the parent component. The `<apex:param>` component can only be a child of the following components:

- `<apex:actionFunction>`
- `<apex:actionSupport>`
- `<apex:commandLink>`
- `<apex:outputLink>`
- `<apex:outputText>`
- `<flow:interview>`

Use this component to get user input for a controller method that does not correspond to a field on an sObject. Only `<apex:inputField>` and `<apex:outputField>` can be used with sObject fields.

Within `<apex:outputText>`, there’s support for the `<apex:param>` tag to match the syntax of the MessageFormat class in Java.

## apex:outputLink Example

```apex
<!-- For this example to render fully, associate the page
with a valid contact record in the URL.
For example: https://MyDomain_login_URL/apex/myPage?id=001D000000IRt53 -->

<apex:page standardController="Contact">
    <apex:outputLink value="http://google.com/search">
        Search Google
        <apex:param name="q" value="{!contact.name}"/>
    </apex:outputLink>
</apex:page>
```

## Attributes

| Attribute Name | Attribute Type | Description                                                                                                                                                                                                                | Required? | API Version | Access |
| -------------- | -------------- | -------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | --------- | ----------- | ------ |
| `assignTo`     | Object         | A setter method that assigns the value of this param to a variable in the associated Visualforce controller. If this attribute is used, getter and setter methods, or a property with get and set values, must be defined. |           | 10.0        | global |
| `id`           | String         | An identifier that allows the param component to be referenced by other components in the page.                                                                                                                            |           | 10.0        | global |
| `name`         | String         | The key for this parameter, for example, name="Location".                                                                                                                                                                  | Yes       | 10.0        | global |
| `value`        | Object         | The data associated with this parameter, for example, value="San Francisco, CA". The value attribute must be set to a string, number, or boolean value.                                                                    | Yes       | 10.0        | global |