Can i use Enum.TryParse in the markup of an ASP.Net page

Question

I read data from an entity framework and bind a repeater on an ASP.NET page (ASPX) to it. One of my fields - iFieldType - contains an integer value which is parsed to an item of an enumeration in the markup of the page like that:

<owiw:CustomTextBox runat="server" ReadOnly="true" ID="txt_FieldType"
                    Text='<%# Enum.Parse(typeof(DatabaseHelper.CustomFieldTypes), Convert.ToString(DataBinder.Eval(Container.DataItem, "iFieldType"))) %>' />

That's because the users don't want to see per example "1" on the page, but the name of the fieldtype "TextBox". Unfortunately iFieldType can be NULL . So i have to replace Enum.Parse by Enum.TryParse . Can this be done in the markup/html?

Answer 1

There are at least two possible solutions.

A) We can program in code-behind of the page a public(!) method which does the tryparse.

Per example:

public string FieldTypeTryParseToString(object value)
{
    if (value == null)
    {
        return "0";
    }

    return value.ToString();
}

Then in the markup we implement the new method:

<owiw:CustomTextBox runat="server" ReadOnly="true" ID="txt_FieldType"
    Text='<%# Enum.Parse(typeof(DatabaseHelper.CustomFieldTypes), FieldTypeTryParseToString(DataBinder.Eval(Container.DataItem, "iFieldType"))) %>' />

B) We can do it in the markup too but it will make the code more complex. In this case we check if the value is null.

<owiw:CustomTextBox runat="server" ReadOnly="true" ID="txt_FieldType"
    Text='<%# Enum.Parse(typeof(DatabaseHelper.CustomFieldTypes), DataBinder.Eval(Container.DataItem, "iFieldType") == null ? "0" : Convert.ToString(DataBinder.Eval(Container.DataItem, "iFieldType"))) %>' />