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c# - mvc 5 SelectList from table with blank value for DropDownList

I am using below code to create a drop down

Controller

ViewBag.Id= new SelectList(db.TableName.OrderBy(x => x.Name),"Id","Name")

View

 @Html.DropDownList("Id", null, htmlAttributes: new { @class = "form-control" })

My question is how can I Modify SelectList to add a blank item so that there is a blank item automatically added for DropDownList.

Thanks.

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Use one of the overloads that accepts an optionLabel

@Html.DropDownListFor(m => m.ID, (SelectList)ViewBag.MyList, "Please select", new { @class = "form-control" })

or if you do not want to use the strongly typed methods

@Html.DropDownList("ID", (SelectList)ViewBag.MyList, "Please select", new { @class = "form-control" })

Which will add the first option with the text specified in the 3rd parameter and with a null value

<option value="">Please Select</option>

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