Hi there,

I too faced many problems in writing the test cases , later i found out how to write these.

I am still a new bee, so please correct me if I am wrong.

In order to write test method for a button click,

first u need to start with calling your contructor

suppose you are wrting test method for a button   click of a standard controller page, for that button clickyou are inserting certain record

object o=new object();

ApexPages.StandardController sc = new ApexPages.StandardController(o);

ClassName cn = new ClassName(sc);

//if you are using any property variable while inserting the record, we just need to assign those properties

cn.property1 = value1;

cn.property2 = value2;

//call the function

cn.function();

//if you are using querystrings then you need to set the current context of the page to accomodate those values

        Object  u =new Object(field1= value1,field2 = value2,field3=value3);
        insert u;

        pagereference pg=new pagereference('/apex/VisualForcePage?id='+u.ID);
        system.test.setCurrentpage(pg);
       

        object o=new object();

        ApexPages.StandardController sc = new ApexPages.StandardController(o);

        ClassName cn = new ClassName(sc);

        cn.property1 = pg.getparameters().get('id'); 

        cn.function();