hi,

i am new to this test classes concept. Can anybody give an example for writing a test class for a controller.

public PageReference psignup() {
    emailerror=false;
        emailacept=false;
        List<guestuser__c> ldtls=[select Id from guestuser__c where Email__c=:email];
        
        if(ldtls.size()>0)
        {
            emailerror=true;
            emailacept=false;
            //uid exist
        }
        else
        {
            if(pwd==rpwd)
            {
                emailerror=false;
                emailacept=false;
                guestuser__c gu=new guestuser__c();
                gu.First_Name__c=fname;
                gu.Password__c=pwd;
                gu.Email__c=email;
                gu.Title__c = job;
                gu.Email_Optout__c = echeck;
                gu.Last_Name__c = lname;
                gu.Company__c = comp;
                gu.Street__c = street;
                gu.State__c = state;
                gu.City__c = city;
                gu.Country__c = ctry;
                gu.Zipcode__c = zip;
                
                
                Lead ld=new Lead();          
                ld.FirstName =fname;
                ld.LastName=lname;
                ld.Company=comp;
                ld.Street=street;
                ld.State=state;
                ld.city=city;
                ld.PostalCode=zip;
                ld.country=ctry;
                ld.Title=job;
                ld.Email=email;
                ld.HasOptedOutOfEmail=echeck;
                
                
                try{
                insert ld;
                insert gu;
                Pagereference pageref=new Pagereference('/apex/thankq');     
                    pageref.setRedirect(true);
                    return pageref;
                }
                catch(Exception e)
                {
                    system.debug(e);
                }
            }
            else
            {
                ApexPages.Message myMsg = new ApexPages.Message(ApexPages.Severity.WARNING, 'PASSWORD MISS-MATCH');
                ApexPages.addMessage(myMsg);
            }
        }
        return null;
    }


    public Boolean echeck { get; set; }

    public String rpwd { get; set; }

    public String pwd { get; set; }

    public void checkavlble() {
        String lusername= Apexpages.currentPage().getParameters().get('mail');
        List<guestuser__c> chkldtls=[select Id from guestuser__c where Email__c=:email];
        if(chkldtls.size()>0)
        {
            emailerror=true;
            emailacept=false;
        }
        else
        {           //try another
            emailerror=false;
            emailacept=true;
        }
    }


    public Boolean emailacept { get; set; }

    public Boolean emailerror { get; set; }

    public String email { get; set; }

    public String job { get; set; }

    public String ctry { get; set; }

    public String zip { get; set; }

    public String state { get; set; }

    public String city { get; set; }

    public String street { get; set; }

    public String comp { get; set; }

    public String lname { get; set; }

    public String fname { get; set; }
}

i need to write the test class for this controller to deploy the page.can anybody help me with an example.