sql server - How to filter displayed products according to their category in C# -

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• how filter displayed products according producttype in tabcontrol- tabpages in c# 4 answers

okay. after several hours of thinking decided ask question again since couldn't make work though had guidance answers in previous question. here's original question

now i'm creating point of sale system , want display products dynamically in database buttons on tabcontrol - tabpages according producttype. problem is, products tabpags buttons can't sort them out each tabpage according producttype same list of products display on every tabpage below.

and database.

private void createtabpages() // create tab pages each producttype         {             con.open();             sqldataadapter sda = new sqldataadapter("select distinct producttype, description tblproducttype", con);             datatable dt = new datatable();             sda.fill(dt);              foreach (datarow dr in dt.rows)             {                 tabcontrol1.tabpages.add(dr["producttype"].tostring(),dr["description"].tostring());             }              con.close();            }       private void addproductstotabbedpanel() // add products tab pages {      foreach (tabpage tp in tabcontrol1.tabpages)     {         con.open();         sqldataadapter sda = new sqldataadapter("select distinct description tblproduct", con);         datatable dt = new datatable();         sda.fill(dt);          flowlayoutpanel flp = new flowlayoutpanel();         flp.dock = dockstyle.fill;          foreach (datarow dr in dt.rows)         {             button b = new button();             b.size = new size(100, 100);             b.text = dr["description"].tostring();              flp.controls.add(b);         }          tp.controls.add(flp);         con.close();     }   } 

i appreciate feedback give me on this.

disclaimer: yes, know op's pictures show winforms, in the other question op stated following tutorial on youtube. thought i'd provide way represent same data using wpf.

you use model display each of datatypes, instead of handling raw data; have @ object-relational mapping, entity-framework, nhibernate, etc.

create product model hold data product table.

public class product {     public int productid {get;set;}     public int producttype { get; set; }     public string description { get; set; }     public double price { get; set; }     public byte[] image { get; set; } } 

create product type model hold data product type table.

public class producttype {     public int producttypeid { get; set; }     public string description { get; set; } } 

create window/usercontrol hold tabcontrol.

<window.resources>     <local:productconverter x:key="productconverter" />     <local:producttypeconverter x:key="producttypeconverter" /> </window.resources> <tabcontrol itemssource="{binding myproducts,              converter={staticresource productconverter}}">         <tabcontrol.itemtemplate>             <datatemplate>                 <textblock>                     <textblock.text>                         <multibinding converter="{staticresource producttypeconverter}">                             <binding path="producttype"/>                             <binding path="datacontext.myproducttypes"                                       relativesource="{relativesource ancestortype={x:type window}}"/>                         </multibinding>                     </textblock.text>                 </textblock>             </datatemplate>         </tabcontrol.itemtemplate>         <tabcontrol.contenttemplate>             <datatemplate>                 <listbox itemssource="{binding}">                     <listbox.itemtemplate>                         <datatemplate>                             <button width="150" content="{binding description}"/>                         </datatemplate>                     </listbox.itemtemplate>                 </listbox>             </datatemplate>         </tabcontrol.contenttemplate>     </tabcontrol> 

using itemtemplate , contenttemplate ensure product objects have same format , styling.

this converter converts entire list of products groups of products based on product type value.

public class productconverter : ivalueconverter {     public object convert(object value, type targettype, object parameter, cultureinfo culture) {         if(value list<product> != null) {             return (value list<product>).groupby(a => new { a.producttype });         }          return null;     }     public object convertback(object value, type targettype, object parameter, cultureinfo culture) {         return null;     } } 

this converter converts product.producttype value producttype.description

public class producttypeconverter : imultivalueconverter {     public object convert(object[] values, type targettype, object parameter, cultureinfo culture) {         if(values[0] != null && values[0] != dependencyproperty.unsetvalue &&             values[1] != null && values[1] != dependencyproperty.unsetvalue) {             string f= (values[1] list<producttype>)                       .where(a => a.producttypeid.equals(values[0]))                       .first().description;             return f;         }          return false;     }     public object[] convertback(object value, type[] targettypes, object parameter, cultureinfo culture) {         return null;     } } 

create properties using in displaying tabcontrol.items.

public list<product> myproducts { get; set; } public list<producttype> myproducttypes { get; set; } 

afterwards, have represent raw data in model format. (my sql bit iffy)

    sqlcommand sqlcmdproducts = new sqlcommand("select * tblproduct", myconnection); sqldatareader productreader = sqlcmdproducts.executereader(); while (productreader.read()) {     myproducttypes.add(new producttype() {     producttypeid = int32.parse(productreader["producttype"].tostring()),     description = int32.parse(productreader["description"].tostring()),     }; }  sqlcommand sqlcmdproducttype = new sqlcommand("select * tblproducttype", myconnection); sqldatareader producttypereader = sqlcmdproducttype.executereader(); while (producttypereader.read()) {     myproducts.add(new product() {     productid = int32.parse(producttypereader["productid"].tostring()),     producttype = int32.parse(producttypereader["producttype"].tostring()),     description = producttypereader["description"].tostring()),     price = double.parse(producttypereader["price"].tostring()),     }; }