Param values are not being passed to the custom controller using commandbutton

Question

Need pro's help. Below are my code snippets. This is what I have tried I have initialized the object Event_Request__c {get; set;} in my controller class. I have created a public method to update the Event Request record. On saving, the VF page and Class both are being saved successfully. However, I am not any data. Please advise what is it that am missing.

Input Field and Commandbutton on VF page:

Input field

<div class="form-group">
     <label for="WBS">WBS:</label>
     <input type="text" placeholder="WBS" class="form-control" id="{WBS}" />
</div>

SubmitRequest Button

<apex:form>
    <apex:commandButton action="{!updateEventRequest}" reRender="pageId" id="SubmitRequest" value="Submit Request" >  
        <apex:param id="InputWBS" value="{WBS}"></apex:param>
    </apex:commandButton>    
</apex:form>

Controller class method

   public PageReference updateEventRequest() {
         sEventRequest.WBS__c= ApexPages.currentPage().getParameters().get('WBS');   
         System.debug('The id for update is WBS = ' + sEventRequest.WBS__c);
          update sEventRequest;
          return null;
  }

Answer 1

To pass data to Apex from VisualForce you should use apex:input* tag, for example, apex:input,apex:inputText or apex:inputField.

in your case, if you want to make that text input, you need to use

<apex:inputText  html-placeholder="WBS" styleClass="form-control" value="{!WBS}" />

If you want to do a lookup:

In both cases ensure that properties have public set, in first case ensure that you have doc-type set. Also, you need to wrap it to apex:form to send data to apex controller.

Here you can find more information about how to use that input: https://developer.salesforce.com/docs/atlas.en-us.pages.meta/pages/pages_compref_input.htm

Update: After comment reread Visualforce page part:

<apex:form>
     <apex:inputText  html-placeholder="WBS" styleClass="form-control" value="{!WBS}" />
    <apex:commandButton action="{!updateEventRequest}" reRender="pageId" id="SubmitRequest" value="Submit Request" />  
    </apex:commandButton>    
</apex:form>

Apex Controller part:

Define property WBS as string

public String WBS{get;set;}

And if you want to use standard SF lookup window -- just use

But ensure that sEventRequest is defined as

public <some type> sEventRequest{get;set;}

and it is initiated in constructor (i.e. not null).