Connect two WebParts, cant get info from my provider to consumer

Question

Got a small problem but don't know how to solve it. Getting the exception:

"Input string was not in a correct format."

I hope someone can take his/her time to read my codes and try to help me solve the problem.

I'm searching through a SharePoint list, listname: "Extern Products" and got the columns: Title, ProductNumber, ListPrice, Color and MoreInformation.

Code Consumer WebPart (SearchWPList.cs:

[ToolboxItemAttribute(false)]
public class SearchWPList : WebPart
{
    // Visual Studio might automatically update this path when you change the Visual Web Part project item.
    private const string _ascxPath = @"~/_CONTROLTEMPLATES/Kingen.Artifacts.WebParts/SearchWPList/SearchWPListUserControl.ascx";
    private Control _control;

    protected override void CreateChildControls()
    {
        Control control = Page.LoadControl(_ascxPath);
        Controls.Add(control);
    }

    protected IProductSearch ProductSearch;

    [ConnectionConsumer("Products")]
    public void SetProduct(IProductSearch product)
    {
        ProductSearch = product;
    }

    protected override void OnPreRender(EventArgs e)
    {
        if(ProductSearch != null)
        {
            ((SearchWPListUserControl)_control).SetProduct(ProductSearch.Name);
            ((SearchWPListUserControl)_control).SetProduct(ProductSearch.MoreInformation);
            ((SearchWPListUserControl)_control).SetProduct(ProductSearch.ProductNumber);
            ((SearchWPListUserControl)_control).SetProduct(ProductSearch.Color);
            ((SearchWPListUserControl)_control).SetProduct(ProductSearch.ListPrice.ToString(CultureInfo.InvariantCulture));
        }
        base.OnPreRender(e);
    }
}

Code SearchWPListUserControl.ascx.cs:

public partial class SearchWPListUserControl : UserControl
{
    protected void Page_Load(object sender, EventArgs e)
    {
    }

    public void SetProduct (string product)
    {
        if (product == "ProductNumber")
        {
            TextBox_ProdNumList.Text = "ProductNumber";
        }
        else if (product == "ListPrice")
        {
            TextBox_ListPriceList.Text = "ListPrice";
        }
        else if (product == "Color")
        {
            TextBox_ColorList.Text = "Color";
        }
        else if (product == "Name")
        {
            TextBox_NameList.Text = "Name";
        }
        else if (product == "MoreInformation")
        {
            TextBox_MoreInfoList.Text = "MoreInformation";
        }
    }
}

Code Provider WebPart (SearchList.cs):

[ToolboxItemAttribute(false)]
public class SearchList : WebPart, IProductSearch
{
    // Visual Studio might automatically update this path when you change the Visual Web Part project item.
    private const string _ascxPath = @"~/_CONTROLTEMPLATES/Kingen.Artifacts.WebParts/SearchList/SearchListUserControl.ascx";
    private readonly Control _prodNum;
    private readonly Control _name;
    private readonly Control _listPrice;
    private readonly Control _moreInformation;
    private readonly Control _color;

    protected override void CreateChildControls()
    {
        Control control = Page.LoadControl(_ascxPath);
        Controls.Add(control);
    }

    public string ProductNumber
    {
        get
        {
            if (_prodNum != null)
                return ((SearchListUserControl) _prodNum).ProductNumber;
            return string.Empty;
        }
    }

    public string Name
    {
        get
        {
            if (_name != null)
                return ((SearchListUserControl)_name).Name;
            return string.Empty;
        }
    }

    public string Color
    {
        get
        {
            if (_color != null)
                return ((SearchListUserControl)_color).Color;
            return string.Empty;
        }
    }

    public decimal ListPrice
    {
        get
        {
            if (_listPrice != null)
                return ((SearchListUserControl)_listPrice).ListPrice;
            return decimal.Parse(string.Empty);
        }
    }

    public string MoreInformation
    {
        get
        {
            if (_moreInformation != null)
                return ((SearchListUserControl)_moreInformation).MoreInformation;
            return string.Empty;
        }
    }

    [ConnectionProvider("Product")]
    public IProductSearch GetProduct()
    {
        return this;
    }
}

Code SearchListUserControl.ascx.cs:

public partial class SearchListUserControl : UserControl
{
    protected void Page_Load(object sender, EventArgs e)
    {          
    }

    protected void Button_Search_Click(object sender, EventArgs e)
    {
        ListBox_List.Items.Clear();

        SPWeb web = SPContext.Current.Web;
        SPList prodList = web.Lists.TryGetList("Extern Products");

        if (prodList != null)
        {
            SPQuery query = new SPQuery();
            query.Query = string.Format("<Where><BeginsWith><FieldRef Name='Title' /><Value Type='Text'>{0}</Value></BeginsWith></Where>", TextBox_Search.Text);
            query.ViewFields = "";

            SPListItemCollection items = prodList.GetItems(query);

            foreach (SPListItem listItem in items)
            {
                ListBox_List.Items.Add(listItem.Title);
            }
        }
    }

    public string ProductNumber { get; set; }
    public string Name { get; set; }
    public decimal ListPrice { get; set; }
    public string MoreInformation { get; set; }
    public string Color { get; set; }

    protected void Button_Edit_Click(object sender, EventArgs e)
    {
        try
        {
            if (ListBox_List.SelectedItem != null)
            {
                Name = ListBox_List.SelectedItem.Text;
                ProductNumber = ListBox_List.SelectedItem.Text;
                ListPrice = decimal.Parse(ListBox_List.SelectedItem.Text);
                MoreInformation = ListBox_List.SelectedItem.Text;
                Color = ListBox_List.SelectedItem.Text;
            }
        }
        catch (Exception x)
        {

            Label_ExtensionList.Text = x.Message;
        }
    }
}

My button search control in SearchListUserControl.ascx.cs works without problems. But i cannot get the provider to provide data i my consumer webpart.

Kind regards, Kristian

Answer 1

I guess this line is throwing error for your case in SearchList.cs-

public decimal ListPrice
{
    get
    {
        if (_listPrice != null)
            return ((SearchListUserControl)_listPrice).ListPrice;
        ***return decimal.Parse(string.Empty);***
    }
}

change return decimal.Parse(string.Empty), it will never work, change it to return decimal.MinValue instead, and add some checking when you use the value

---

Though I dont get what you are trying to achieve with this method, but you can use TryParse to distinguish between pure string and number, may be like this -

    public void SetProduct(string product)
    {
        decimal ListPrice;
        if(decimal.TryParse(product, out ListPrice)
        {
            TextBox_ListPriceList.Text="ListPrice";
        }
        else
        {
            if (product == "ProductNumber")
            {
                TextBox_ProdNumList.Text = "ProductNumber";
            }            
            else if (product == "Color")
            {
                TextBox_ColorList.Text = "Color";
            }
            else if (product == "Name")
            {
                TextBox_NameList.Text = "Name";
            }
            else if (product == "MoreInformation")
            {
                TextBox_MoreInfoList.Text = "MoreInformation";
            }
        }            
    }

Answer 2

to put it simple your missing the interface class. Its the middle man that connects the two webparts together (provider to the consumer).

the class will look somthing like this:

using System;
using System.Collections.Generic;
using System.Text;

namespace CommunicationInterface
{
   public interface ICommunicationInterface
   {
        int bookID
        {
            get;
        }

        string bookName
        {
            get;
        }
   }
}

build this simple project with the varibles that you want to pass (int, string, bool) and build that project. Then get the dll and add it to the references in the provider and consumer class so you can access those varibles. Also add the dll to GAC :)

for mode detail on this refer to this guide:

http://msdn.microsoft.com/en-us/library/ms469765.aspx

hope it helps :)

Answer 3

After ages of googling i found an easier way for my webparts to communicate, you can use connectable webparts, to connect them but i didn't solve that, so i've removed my consumer webpart from the site (not code), and typed this code:

    protected void Button_Edit_Click(object sender, EventArgs e)
    {  
        if (ListBox_List.SelectedItem != null)
        {
            WP_ConsumerSearchListUserControl control = (WP_ConsumerSearchListUserControl)Page.LoadControl(@"~/_CONTROLTEMPLATES/Kingen.Artifacts.WebParts/WP_ConsumerSearchList/WP_ConsumerSearchListUserControl.ascx");
            control.GetProduct(ListBox_List.SelectedValue);
            Controls.Add(control);
        }
    }

Hope it helps.