Returning an HtmlTable to be written with ajax.

Question

I'd like to programmatically build an HtmlTable/Table in the code behind of a webservice and have it return as a string of HTML so that it can be written with JavaScript to the innerhtml of a span/div/whatever

Something similar to the following:

//webservice.amsx.cs Build the table, called by another/different method
protected string Table_Maker()
{   
HtmlTable tbl = new HtmlTable();
HtmlTableCell cell = new HtmlTableCell();
HtmlTableRow row = new HtmlTableRow();
cell.InnerText = "WhateverText";    
row.Cells.Add(cell);
tbl.Rows.Add(row);

return tbl.ToString();
}

//somepage.aspx write table to the div
function menuHelper(toplayer, toplayernumber) 
{
    var sublayertable;
    var sublayerpostcompileID;
    var toplayernumber;

    menuHelper_Part1();

    function menuHelper_Part1() 
    {

    //replace ucMainMenu with ucMainMenu_pnlContent
    sublayerpostcompileID = toplayer.replace("ucMainMenu", "ucMainMenu_pnlContent");
    //Call the webmethod
    webbernetz.MenuHelperWebService.Sub_Menu_Helper(toplayernumber, menuHelper_Part2);     
    }

    function menuHelper_Part2(result){
    //Write the result to the target area
    document.getElementById(sublayerpostcompileID).innerHTML = result;
    }
}

When I return it to the javascript the javascript simply writes "System.Web.UI.HtmlControls.HtmlTable".

How di I get it to write the actual table?

Answer 1

There is a RenderControl() method that you can call on any control. Or if you are not using HtmlTable to do anything with it other then building HTML then use HtmlTextWriter.

Answer 2

The problem here is that the HtmlTable.ToString method that you are using is not appropriate for what you want. 'ToString' returns a String that represents the current Object. In this case you have to Render the table first to an HTMLTextWriter and then you can use the method ToString.

Answer 3

Just use tbl.InnerHtml, instead of ToString

Answer 4

Sounds like you are making it more complicated than it needs to be. How about not using the HtmlTable object and just building a string containing the html you need to output.

Answer 5

The only issue with your code is the use of "tbl.ToString()".

As noted in some of the other posts, you should Render the table control using an HtmlTextWriter to a StringBuilder object, which can then return a string value for your method. Something like this:

protected string Table_Maker() {
    HtmlTable tbl = new HtmlTable();
    HtmlTableCell cell = new HtmlTableCell();
    HtmlTableRow row = new HtmlTableRow();
    cell.InnerText = "WhateverText";
    row.Cells.Add(cell);
    tbl.Rows.Add(row);

    StringBuilder sb = new StringBuilder();
    using( StringWriter sw = new StringWriter( sb ) ) {
        using( HtmlTextWriter tw = new HtmlTextWriter( sw ) ) {
            tbl.RenderControl( tw );
        }    
    }    
    return sb.ToString();
}

That should return the HTML to be inserted into your page.