Control creation based on model value in MVC4

Question

In my database, i have a column called control_id which consists value like 1,2,3,4. Based on this value, i have to generate controls like Text box, Dropdownlist and Check box. (For example, if my control_id is 1, has to generate Text box, and for 2, dropdownlist and so on) I am completely new to MVC. Can anyone point me in right direction to implement this scenario?

Answer 1

1. Create an enum for control types

   public enum ControlTypes  
   {
       TextBox  = 1,
       Dropdown = 2,
       CheckBox = 3,
       Label = 4
       // Define other control types  
   }
   

2. Create Baseclass for handling all control types.

   public class DynamicControlsBase
   {
       public virtual string FieldLabel { get; set; }
   
       public string ControlValue { get; set; }
       // For dropdown
       public virtual List<SelectListItem> ValueList { get; set; }
   
       // Likewise implement the other required property that the control uses
   }
   

3. Create a View Model for each control, now for textbox

    // Textbox deriving class    
    public class TextBoxViewModel : DynamicControlsBase 
    {
        public override string FieldLabel
        {
        get
        {
            return base.FieldLabel;
        }
        set
        {
            base.FieldLabel = value;
        }
   }
   
   public override List<SelectListItem> ValueList
   {
       get
       {
           return base.ValueList;
       }
       set
       {
           base.ValueList = value;
       }
   } 
   
   //View model for Label field 
   public class LabelViewModel : DynamicControlsBase 
   {
       public override string FieldLabel { get; set; } 
   }
   

4. Create a View Model for each control, here for dropdown.

   public class DropdownViewModel : DynamicControlsBase   
   {
       public override string FieldLabel { get; set; }
   
       public override List<SelectListItem> ValueList
       {
           get
           {
               return base.ValueList;
           }
           set
           {
           base.ValueList = value;
           }
       }
   }
   

5. Now create a folder named 'EditorTemplates' under Views>>Shared.

6. In that folder create a view for each view model (Textbox and dropdown and more) with the same name as the ViewModel ex. TextBoxViewModel.cshtml, and do the same for dropdown and other controls.

    @model MVCSample.Models.TextBoxViewModel 
    @Html.TextBoxFor(m => m.ControlValue)
   

7. In the controller action method assign the value for each respective view model like below and pass it to the view.

   DynamicControlsBase dcb = new TextBoxViewModel
   {
       ControlValue = "Test"
   };
   
   dcb = new DropdownViewModel
   {
        ControlValue = "Test",
        ValueList = new List<SelectListItem>
        {
             new SelectListItem
             {
                  Text = "Test",
                  Value= "1"
             },
             new SelectListItem
             {
                  Text = "Text",
                  Value= "1"
             }
        }
   };
   

8. In the actual view, render the controls using html helper 'EditorFor',

   @Html.EditorFor(m => m.DynamicControlsBase)
   

In controller modify the GetControl method as,

private DynamicControlsBase GetControl(string controlType, DataTable tableData = null, List<SelectListItem> controlValue = null)
{
    if (controlType.Equals(Convert.ToString((int)ControlTypes.TextBox)))
    {
        return new TextBoxViewModel
        {
            ControlValue = tableData.AsEnumerable().Where(a => a.Field<int>("Control_id").Equals(int.Parse(controlType))).Select(a => a.Field<string>("Value")).FirstOrDefault(),
            FieldLabel = tableData.AsEnumerable().Where(a => a.Field<int>("Control_id").Equals(int.Parse(controlType))).Select(a => a.Field<string>("FieldLabel")).FirstOrDefault()
        };
    }
    else if (controlType.Equals(Convert.ToString((int)ControlTypes.Dropdown)))
    {
        return new DropdownViewModel
        {
            ControlValue = tableData.AsEnumerable().Where(a => a.Field<int>("Control_id").Equals(int.Parse(controlType))).Select(a => a.Field<string>("Value")).FirstOrDefault(),
            FieldLabel = tableData.AsEnumerable().Where(a => a.Field<int>("Control_id").Equals(int.Parse(controlType))).Select(a => a.Field<string>("FieldLabel")).FirstOrDefault(),
            ValueList = controlValue
        };
    }
    if (controlType.Equals(Convert.ToString((int)ControlTypes.Label)))
    {
        return new LabelViewModel
        {
            ControlValue = tableData.AsEnumerable().Where(a => a.Field<int>("Control_id").Equals(int.Parse(controlType))).Select(a => a.Field<string>("Value")).FirstOrDefault(),
            FieldLabel = tableData.AsEnumerable().Where(a => a.Field<int>("Control_id").Equals(int.Parse(controlType))).Select(a => a.Field<string>("FieldLabel")).FirstOrDefault()
        };
    }

    return new DynamicControlsBase();
}