How to filter records in the form by code in Ax 2009

Hi friends we are going to filter the records in the form by using the code in Ax 2009
Step 1: Declare a class variable
In the ClassDeclaration method of the form, define a range.

QueryBuildRange CurrencyQBR;

Step 2: Instantiate the new range.
In the init method on the datasource of the form, you assign the range to a specific field (after the super call).

public void init()
{
super();

CurrencyQBR = this.query().dataSourceName('CustTable').addRange(fieldnum(CustTable,Currency));
}
Step 3: In the last step, you assign a value to the range.
This is done in the executeQuery method on the same datasource of the form. Before the super call. Like this:

public void executeQuery()
{ ;

CurrencyQBR.value(queryvalue('USD'));

super();
}
    By this you can filter record
                                                     Vivek Chirumamilla