<apex:page controller="Saved" showHeader="false" sidebar="false">
<apex:form id="ss" > 
<apex:messages ></apex:messages>
<apex:pageblock >
<apex:pageblockSection >
<apex:pageBlockSectionItem >Name:</apex:pageBlockSectionItem>
<apex:pageBlockSectionItem ><apex:inputText value="{!name}" id="name" required="true" /></apex:pageBlockSectionItem>
<apex:pageblockSectionItem >Date:</apex:pageblockSectionItem>
<apex:pageblockSectionItem ><apex:inputtext onfocus="DatePicker.pickDate(true, this , false);" value="{!dat}" id="dt"/></apex:pageblockSectionItem>
<apex:pageblockSectionItem >Age:</apex:pageblockSectionItem>                       
<apex:pageblockSectionItem ><apex:outputText value="{!age}" /></apex:pageblockSecti
<apex:pageBlockSectionItem >Address:</apex:pageBlockSectionItem>
<apex:pageBlockSectionItem ><apex:inputText value="{!address}"/></apex:pageBlockSectionItem>
<apex:pageBlockSectionItem >City:</apex:pageBlockSectionItem>
<apex:pageBlockSectionItem ><apex:inputText value="{!city}"/></apex:pageBlockSectionItem>
</apex:pageblockSection>
<apex:pageblockButtons Location="bottom" >
<apex:commandButton value="save" action="{!find}"/>
</apex:pageblockButtons>
</apex:pageblock>
</apex:form>   
<apex:outputLabel value="{!name}"></apex:outputLabel><br/>
<apex:outputlabel value="{!dat}"></apex:outputlabel><br/>
<apex:outputlabel value="{!age}"></apex:outputlabel><br/>
<apex:outputlabel value="{!address}"></apex:outputlabel><br/>
<apex:outputlabel value="{!city}"></apex:outputlabel><br/>        
</apex:page>



public class Saved 
{  
    public string name{get;set;}
        
    public Date dat {get;set;}
    public Integer age {get;set;}    
    public string address{get;set;}
    public string city{get;set;}
    public void find()
    {
        Integer temp = dat.daysBetween(Date.Today());
        age = Integer.valueOf(temp/365);
    }
   }
     




in this i want to do the validation for the name field(it should not contain any numbers ar special characters).if we enter any number it should shoew alert.only alphabets can enter