Make visualforce page read only

Question

I want make a page read only. This is the code I've tried:

<apex:page showheader="false" sidebar="false" id="page" extensions="test"
    standardcontroller="test__c" readOnly="true">
  <apex:form >
    <apex:pageBlock id="pbCustomerDetails">
      <apex:pageBlockSection columns="1" collapsible="false">
        <apex:inputField value="{!test.Legal_Name_in_English__c}" label="Name of Customer"/>
        <apex:inputCheckbox value="{!test.Legal_Name_Checkbox__c}" label="legal name" />
        <apex:inputField value="{!test.Legal_Name_in_Local_Language__c}" rendered="{!(test.Legal_Name_Checkbox__c == true)}" /> 
      </apex:pageBlockSection>
    </apex:pageBlock>
  </apex:form>
</apex:page>

The readonly="true" property of <apex:page> is not making the entire page read only, can somebody explain why?

Answer 1

Use <apex:outputfield> instead of <apex:inputfield> wherever you are trying to accept input.

Quoting from Documentation, this is what readonly does

A Boolean value that enables read-only mode for a Visualforce page. In read-only mode, a page may not execute any DML operations, but the limit on the number of records retrieved is relaxed from 50,000 to 1 million rows. It also increases the number of items in a collection that can be handled by iteration components, from 1,000 to 10,000. If not specified, this value defaults to false.

I am not aware of any other way of making the page not accepting inputs. In readonly mode even though you can accept inputs no DML operations are performed