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DataTable checking if null returns an error but not on variable declaration

I have this weird error.
On this code, as you can, I have a query on database, return it as DataTable and explicitly declared it null. Now I have a condition to check this if this is null and pass it to a string variable. Everything works fine. I receive an empty string. No exception found.
DataTable dtDateUploaded = _BL.GetRecordByDataTableResults();
dtDateUploaded = null;
string strUploadedDate = dtDateUploaded == null ? string.Empty :
dtDateUploaded.Rows[0].IsNull(0) ? string.Empty :
dtDateUploaded.Rows[0][0].ToString();
But when I used the same condition and pass it directly to a Label control for example (and not use a string variable), I get an object reference error. I wonder why do I get an object reference error if I just used the same code on my string variable above?
LblRecordCount.Text = "Record Uploaded last: " + dtDateUploaded == null ? string.Empty :
dtDateUploaded.Rows[0].IsNull(0) ? string.Empty :
dtDateUploaded.Rows[0][0].ToString();
And the weird part is that this works:
LblRecordCount.Text = "Record Uploaded last: " + strUploadedDate;

You get this error because, in the second example, the + operator has precedence over the == operator so you are trying to concatenate the "Record Uploaded last" string to a null variable.
Instead, in the first example, the = operator has lower precedence than the == operator and no error occurs because the ternary operators are evaluated before the assignment.
You should use brackets to group the ternary operators logic together
LblRecordCount.Text = "Record Uploaded last: " + (dtDateUploaded == null ? string.Empty :
dtDateUploaded.Rows[0].IsNull(0) ? string.Empty :
dtDateUploaded.Rows[0][0].ToString());
See MSDN on C# Operators

Is there a shorthand for the ternary operator in C#?

Background
In PHP there is a shorthand for the ternary operator:
$value = "";
echo $value ?: "value was empty"; // same as $value == "" ? "value was empty" : $value;
In JS there's also an equivalent:
var value = "";
var ret = value || "value was empty"; // same as var ret = value == "" ? "value was empty" : value;
But in C#, there's (as far as i know) only the "full" version works:
string Value = "";
string Result = Value == string.Empty ? "value was empty" : Value;
So my question is: Is there a shorthand for the ternary operator in C#, and if not, is there a workaround?
Research
I found the following questions, but they're referring to use the ternary operator as shorthand to if-else:
shorthand If Statements: C#
Benefits of using the conditional ?: (ternary) operator
And this one, but it's concerning Java:
Is there a PHP like short version of the ternary operator in Java?
What I have tried
Use the shorthand style of PHP (Failed due to syntax error)
string Value = "";
string Result = Value ?: "value was empty";
Use the shorthand style of JS (Failed because "The || operator is not applicable to string and string.")
string Value = "";
string Result = Value || "value was empty";

There is no shorthand for when the string is empty. There is a shorthand for when the string is null :
string Value = null;
string Result = Value ?? "value was null";

The coalesce ?? operator works only on null, but you could "customize" the behavior with an extension method:
public static class StringExtensions
{
public static string Coalesce(this string value, string #default)
{
return string.IsNullOrEmpty(value)
? value
: #default;
}
}
and you use it like this:
var s = stringValue.Coalesce("value was empty or null");
But I don't think it is much better than the ternary.
Note: the # allows you to use reserved words as variable names.

vb.net to c# conversion for IsDBNull not working

The following conversion doesn't work.
Error:"Only assignment, call, increment, decrement & new object can be
used as a statement"
VB.net
objUser.Email = IIf(IsDBNull(drow("Email")), "", drow("Email"))
C#
objUser.Email == (Information.IsDBNull(drow("Email")) ? "" : drow("Email"));
I need it in C#. Any ideas??

In C# = is asignment operator and == is comparison operator
Remove == and replace with =.
Assuming that drow is DataRow
objUser.Email = (drow.IsNull("Email") ? String.Empty : drow["Email"].ToString());
?: is ternary operator which always returns a value. In your case that value is being assigned to objUser.Email.

You have accidentally, used comparison operator instead of assignment operator.
objUser.Email == (Information.IsDBNull(drow("Email")) ? "" : drow("Email"));
should be, as you are not doing comparision, its an assignment.
objUser.Email = (Information.IsDBNull(drow("Email")) ? "" : drow("Email"));

You're using equal operator instead of assignment operator in the C# variant.
Change the == to = since what you want is assignment.
objUser.Email = (Information.IsDBNull(drow("Email")) ? "" : drow("Email"));

Try this:
objUser.Email = (DBNull.Value == drow("Email")) ? "" : drow("Email"));
See the Documentation for DbNull - where you will find examples:
From MSDN
private string AddFieldValue(string label, DataRow row,
string fieldName)
{
if (! DBNull.Value.Equals(row[fieldName]))
return (string) row[fieldName] + " ";
else
return String.Empty;
}

How do I convert a database number to hex when the field might be null?

I have trouble to convert from decimal to hex.
Here is my code:
select new
{
MessageID = table1.Field<Int32?>("MessageID"),
MessageIDHex = (String)table1.Field<Int32>("MessageID").ToString("X")
}
It gives me Error
with DBNUll.Value cant not change to System.In32
So I have tried
MessageIDHex= (String)table1.Field<Int32?>("MessageID").ToString("X")}
but it gives me another error.
How can I fix it or it does have another way to solve it.

Apparently, MessageID can be DBNull. The simplest solution is to read the value as a nullable int (to prevent the conversion error from occurring). If you use Field with a nullable type, DBNull is automatically converted to null, which can then be coerced to 0 with the ?? operator:
MessageIDHex = (table1.Field<Int32?>("MessageID") ?? 0).ToString("X")
Alternatively, if you prefer, you can have DBNull values in the database result in an empty or a null string for MessageIDHex:
MessageIDHex = table1.IsNull("MessageID") ? "" : table1.Field<Int32>("MessageID").ToString("X")
MessageIDHex = table1.IsNull("MessageID") ? null : table1.Field<Int32>("MessageID").ToString("X")

Conditional variables

I'm missing something, how do I make this work?
var now = DateTime.Now;
string loadStartDate = Request.QueryString["sd"] == String.Empty ? now.AddMonths( -14 ).ToShortDateString();
string loadEndDate = Request.QueryString[ "ed" ] == String.Empty ? now.ToShortDateString();
Basically when the page loades if sd and/or ed is blank, then fill the date with my pre-defined stuff.

You are forgetting a : and the part after it.
The conditional operator has three parts:
predicate (Request.QueryString["sd"] == String.Empty)
true branch
false branch
You are missing the false branch syntax and value.
I would write it as:
string loadStartDate = string.IsNullOrWhitespace(Request.QueryString["sd"])
? now.AddMonths( -14 ).ToShortDateString()
: Request.QueryString["sd"];
Note:
string.IsNullOrWhitespace is new to .NET 4.0, so use string.IsNullOrEmpty for prior versions.

It should be like:
string loadStartDate = Request.QueryString["sd"] == String.Empty ? now.AddMonths
( -14 ).ToShortDateString():SOME OTHER VALUE;

The syntax for the conditional operator is:
condition ? truevalue : falsevalue
You are missing the colon and the value for when the conditon is false.
You can use the conditional operator for this, but then it gets a little repetetive. Just do like this:
DateTime now = DateTime.Now;
string loadStartDate = Request.QueryString["sd"];
if (String.IsNullOrEmpty(loadStartDate)) loadStartDate = now.AddMonths(-14).ToShortDateString();
string loadEndDate = Request.QueryString[ "ed" ];
if (String.IsNullOrEmpty(loadEndDate)) loadEndDate = now.ToShortDateString();