I wanted to modify the Site.createPortalUser(u,accountId, password) to meet my requirment ? Can we do that if yes than How ?
Please suggest. Thanks in advance.

I have created a dependent pick list. I am populating the cities name based on the state but it is not working here is my code

<apex:pageBlock Title="New Case" mode="edit" id="Block">
        <apex:pageBlockSection title="Case Information" id="Block1" columns="2">

            <apex:pageblockSectionItem >
                <apex:outputLabel value="Status"/>
                <apex:outputText value="New"/>
            </apex:pageblockSectionItem>
            
            <apex:pageblockSectionItem >
                <apex:outputLabel value="Priority"/>
                <apex:selectList size="1" value="{!priority}">
                    <apex:selectOptions value="{!priorities}"/>
                </apex:selectList>
            </apex:pageblockSectionItem>
            <apex:pageblockSectionItem >
                <apex:outputLabel value="State"/>
                <apex:selectList size="1" value="{!state1}">
                    <apex:selectOptions value="{!states1}"/>
                    <apex:actionSupport event="onchange" reRender="a"/>
                </apex:selectList>               
            </apex:pageblockSectionItem>
            <apex:outputPanel id="a">
            <apex:pageblockSectionItem >
                <apex:outputLabel value="City"/>
                <apex:selectList size="1" value="{!city1}" id="a1">
                    <apex:selectOptions value="{!cities1}"/>
                </apex:selectList>
            </apex:pageblockSectionItem>
                </apex:outputPanel>
            </apex:pageBlockSection>

Thanks in advance.!!!

I have created a dependent pick list. I am populating the cities name based on the state but it is not working here is my code

<apex:pageBlock Title="New Case" mode="edit" id="Block">
        <apex:pageBlockSection title="Case Information" id="Block1" columns="2">

            <apex:pageblockSectionItem >
                <apex:outputLabel value="Status"/>
                <apex:outputText value="New"/>
            </apex:pageblockSectionItem>
            
            <apex:pageblockSectionItem >
                <apex:outputLabel value="Priority"/>
                <apex:selectList size="1" value="{!priority}">
                    <apex:selectOptions value="{!priorities}"/>
                </apex:selectList>
            </apex:pageblockSectionItem>
            <apex:pageblockSectionItem >
                <apex:outputLabel value="State"/>
                <apex:selectList size="1" value="{!state1}">
                    <apex:selectOptions value="{!states1}"/>
                    <apex:actionSupport event="onchange" reRender="a"/>
                </apex:selectList>               
            </apex:pageblockSectionItem>
            <apex:outputPanel id="a">
            <apex:pageblockSectionItem >
                <apex:outputLabel value="City"/>
                <apex:selectList size="1" value="{!city1}" id="a1">
                    <apex:selectOptions value="{!cities1}"/>
                </apex:selectList>
            </apex:pageblockSectionItem>
                </apex:outputPanel>
            </apex:pageBlockSection>

Thanks in advance.!!!