How to Create Dynamic Fields Form Since XML File

Depending on the customer, sometimes you don´t know the controls that you must show, load or render in your .NET application.

A good way is having an XML file depending on the customer and you will load your page dynamically and your controls (this example in C#).

This is an example of XML configuration file where there is only one customer (Customer1):

<Centers>
    <Center Name="Customer1>">
        <Field Name="Customer Number" 
        Tipo="String"  Id="CustomerNumber"></Campo>
        <Field Name="Customer City" 
        Tipo="String"  Id="CustomerCity"></Campo>
    </Center>
</Centers>

You will need and empty Panel object in your aspx page.

<asp:Panel runat="server" ID="panelControls" Width="250px">
    </asp:Panel>

In my example, I have Telerik components, but you can use ASP.NET component without problems.
The method you can use in your code behind (load event, init event … ) could be something like that:

using System.Web.UI;
using System.Web.UI.WebControls;
using System.Web.UI.HtmlControls;
using Telerik.Web.UI;  // if you work with Telerik
....
protected void BuildPanel()
{
    controls = new List<Control>();

    XElement xmlControls = XElement.Load(MapPath("~/XML/ImportacionHosp.xml"));

    XElement fieldsCenter = xmlControls.Elements("Center").SingleOrDefault
				(e => e.Attribute("Name").Value == "Customer1");

    HtmlGenericControl auxTable = new HtmlGenericControl("table");
    auxTable.Style.Add("text-align", "left");

    foreach (XElement field in fieldsCenter.Elements())
    {
        HtmlGenericControl auxTr = new HtmlGenericControl("tr");
        HtmlGenericControl auxTh = new HtmlGenericControl("th");
        HtmlGenericControl auxTd = new HtmlGenericControl("td");

        switch (field.Attribute("Tipo").Value)
        {
            case "Int32":
                RadNumericTextBox auxNum = new RadNumericTextBox();
                auxNum.MinValue = 0;
                auxNum.MaxValue = 99999;
                auxNum.NumberFormat.DecimalDigits = 2;
                auxNum.DataType = Type.GetType("Int32");
                auxNum.ID = field.Attribute("Id").Value;

                controls.Add(auxNum);
                auxTd.Controls.Add(auxNum);
                break;

            case "String":
                RadTextBox auxText = new RadTextBox();
                auxText.MaxLength = int.Parse(field.Attribute("MaxLength").Value);
                auxText.ID = field.Attribute("Id").Value;

                controls.Add(auxText);
                auxTd.Controls.Add(auxText);
                break;

            case "DateTime":
                RadDateInput auxDate = new RadDateInput();
                auxDate.ID = field.Attribute("Id").Value;

                controls.Add(auxDate);
                auxTd.Controls.Add(auxDate);
                break;

            default:
                 // launch exception.
        }

        auxTr.Controls.Add(auxTh);
        auxTr.Controls.Add(auxTd);
        auxTable.Controls.Add(auxTr);
    }
  panelControls.Controls.Add(auxTable);
}

You can improve it adding in XML file parameters as MaxLength, MaxValue, … and controlling in BuildPanel() method.

If this post helped you, please leave a comment.

Filed under: .NET, CodeProject, Telerik, Visual Studio