Request Variables

Sometimes it's useful for a template to access the request variables that were submitted in a form. For example, sometimes you want to redisplay the form with user's input still in the fields. If you're writing such a page, you can construct a freemarker.ext.servlet.HttpRequestParametersHashModel, which wraps form parameters back into your data model so they can be used to set default values of form fields. Parameters with single values are wrapped as scalars; parameters with multiple values are wrapped as lists of scalars, with the first value wrapped as a scalar. For instance, if you created a HttpRequestParametersHashModel and put it into your data model with the name "request", here's an example of how you could use this to redisplay a text field and give it the submitted value:

<input type="text" name="foo" size="20" value="${request.foo}">

Here's an example with checkboxes:

<input type="checkbox" name="foo" value="checked" ${request.foo}>Foo<br>
<input type="checkbox" name="bar" value="checked" ${request.bar}>Bar<br>

With radio buttons:

<input type="radio" name="foo" value="yes" <if request.foo == "yes">checked</if>>Yes<br>
<input type="radio" name="foo" value="no" <if request.foo == "no">checked</if>>No<br>

A single-selection pull-down menu:

<select name="foo">
    <option value="yes" <if request.foo == "yes">selected</if>>Yes
    <option value="no" <if request.foo == "no">selected</if>>No
</select>

A single-selection pull-down menu whose values come from your data model:

<select name="foo">
    <list fooOptions as fooOption>
        <option value="${fooOption}"
        <if request.foo == fooOption>selected</if>>${fooOption}
    </list>
</select>

A multiple-selection pull-down menu whose values come from your data model:

<select name="foo" size="5" multiple>
    <list fooOptions as fooOption>
        <option value="${fooOption}"
            <list request.foo as fooSelection>
                <if fooOption == fooSelection>selected</if>
            </list>
        >${fooOption}
    </list>
</select>

Since a scalar can be treated as a list with one element, this will work even if the user selects only one value.

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