How i can extend Sales Invoice Item

Anyone know how can i extend SalesInvoiceItem thanks

Not sure what you mean by this, if you mean you want to add new columns, you can go to Customize Form and select the doctype to customize.

Hi @Pawan I try create my own method to calculate to price item but this code don´t worked

erpnext.accounts.SalesInvoiceItem = frappe.ui.form.Controller.extend({
item_code:function(frm, cdt, cdn){
var d = locals[cdt][cdn];
if (d.item_code) {
frappe.db.get_value(“Item”, {“item_code”: d.item_code}, [“list_price”,“list_price_with_tax”], function (r) {
d.rate=r.list_price_with_tax;
frm.refresh_field(“items”)
})
}
}
});
$.extend(cur_frm.cscript, new erpnext.accounts.SalesInvoiceItem({frm: cur_frm}));