Answer

Custom Web Part with CheckBoxList values lost on PostBack.

Swetha Sankaran

15y

5.8k

Hi all,

I am trying to pass filter values from a custom webpart to a consumer web part. The passed vlaues are listed in a CheckBoxList. The databinding occurs in the GetValues method.

I have 2 issues:

a) When i select the values from the consumer web part(checkboxlist) and hit apply(i have added a imagebutton with autopostback attribute set to true) the checked values appear in a comma seperated string within a textbox but the values are lost after postback.

b) If I take the databind from getvalues and put it in Page_LoadComplete with if(!this.Page.IsPostBack) then, the values dont even appear in the checkboxlist.

How do i resolve this issue?

I'm pretty stumped. I've been staring at this thing for over 2 days now. Please find attached the code i'm working with. There is a javacript handler attached to the checkboxlist that correctly identifies the values selected. I guess it gets messed up on PostBack event.

        [ConnectionConsumer("Input Values")]
        public void GetValues(ITransformableFilterValues values)
        {
            foreach (string val in values.ParameterValues)
                {
                    //this.Provider_Values += this.Provider_Values != " " ?","+ "'" + val +"'" : "'" + val + "'" ;
                    this.Provider_Values = val;
                    this.Provider_Name = values.ParameterName;
                    ds = new SqlDataSource();
                    ds.ID = "Source ID";
                    ds.ConnectionString = cString;

ds.SelectCommand = this.SQLSelectCommand;//"select distinct " + cName +
" from " + tName + " where " + this.Provider_Name+ " = '" +
this.Provider_Values+ "';";
                    cBList.DataTextField = cName;
                    cBList.DataValueField = cName;
                    cBList.DataSource = ds;
                    cBList.ID = "List ID";
                    cBList.Attributes.Add("onclick", "FindSelectedItems(this," + tB.ClientID + ");");
                    cBList.DataBind();
                }
            
        }
         public void BuildControls()
            {  
            try
            {
                cBList = new CheckBoxList();
                this.Controls.Add(cBList);
            }
            //Sql exception cought.
            catch (Exception ex)
            {
                ex1 = ex.Message;
            }
        }
 
        protected override void CreateChildControls()
        {
            this.BuildControls();
            base.CreateChildControls();
        }
 
        protected override void OnInit(EventArgs e)
        {
            this.Page.LoadComplete += new EventHandler(Page_LoadComplete);
            base.OnInit(e);
        }
        
        void Page_LoadComplete(object sender, EventArgs e)
        {

if (this.Page.IsPostBack &&
!String.IsNullOrEmpty(this.Provider_Name) &&
String.IsNullOrEmpty(this.Provider_Values))
            {

ds.SelectCommand = "select distinct " + cName + " from " + tName + "
where " + this.Provider_Name + " = '" + this.Provider_Values + "';";
                
            }
         
        }