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Ternary operator; What is wrong with this syntax?

I am trying to create MailMessage and I am getting the following error ...

Cannot implicitly convert type 'string' to 'bool'

This is my init statement:

MailMessage msg = new MailMessage("DoNotReply@optoma.com",
                      myTbl.Rows[i]["Requester"].ToString().Trim(),
                      subject, 
                      "Dear " + myTbl.Rows[i]["Ship_Attention"].ToString() + ",<br/><br/>" +
                      body + "<br/>Your ISO ID is " + myTbl.Rows[i]["ISO_ID"].ToString() + 
                      (Convert.ToInt32(myTbl.Rows[i]["EmailType"]) == 1) ? 
                          ("<br/>Tracking Number: " + myTbl.Rows[i]["Tracking_No"].ToString()) : 
                          ("") + "<br/><br/>Please examine the loaned items for this transaction:<br/><br/>" +
                      sw.ToString());

I am trying to add a string at runtime based on a boolean expression. Why can't I do this? Am I not doing it right?

string + (true | false) ? "somestring" : "anotherstring" + string
+3
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5 answers

?: The operator has a very low priority. Put it in parentheses, and I think you will solve your problem.

((true|false)?"somestring":"anotherstring")
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When you have it string + (bool)?"somestring":"anotherstring" + string, +gets an estimate before ?, so you need parentheses:

string + ((bool)?"somestring":"anotherstring") + string

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....

  void SendMessage(DataRow  row, string subject, string body, string sw)
    {
        var to = row["Requester"].ToString().Trim();
        var isoId = row["ISO_ID"].ToString();
        var attention = row["Ship_Attention"].ToString();
        var emailType = Convert.ToInt32(row["EmailType"]);
        var message = (emailType == 1) ? ("<br/>Tracking Number: " + row["Tracking_No"]) : ("");
        MailMessage msg = new MailMessage("DoNotReply@optoma.com",
                  to,
                  subject, 
                  string.Format("Dear {0},<br/><br/>{1}<br/>Your ISO ID is {2}{3}<br/><br/>Please examine the loaned items for this transaction:<br/><br/>{4}",
                                attention, body, isoId, message, sw));
    }
+2

, - +. :

string + (true|false ? "somestring" : "anotherstring") + string

:

MailMessage msg = new MailMessage("DoNotReply@optoma.com", myTbl.Rows[i]["Requester"].ToString().Trim(),
subject, "Dear " + myTbl.Rows[i]["Ship_Attention"].ToString() + ",<br/><br/>" +
body + "<br/>Your ISO ID is " + myTbl.Rows[i]["ISO_ID"].ToString() + (Convert.ToInt32(myTbl.Rows[i]["EmailType"]) == 1 ? ("<br/>Tracking Number: " + myTbl.Rows[i]["Tracking_No"].ToString()) : ("")) + "<br/><br/>Please examine the loaned items for this transaction:<br/><br/>" +
sw.ToString());

, , , , .

0

oprator (+) , (?:), : http://msdn.microsoft.com/en-us/library/aa691323%28v=vs.71%29.aspx.

:

string + ((true|false)?"somestring":"anotherstring") + string

, string.format(), clener. .

0

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