EvaluateException at Select-Funktion

der flori

Hi, I´d like to select DataRows with an Id and a Date, but I always get the following Error-Message: Cannot perform '=' operation on System.DateTime and System.String. Here my Code:

string BehID = data1.Behandlungen.Rows.Count.ToString();
string datum = microsim1["picdate"].ToString();
DataRow[] VerlaufDatum = data1.Verlauf.Select("BehandlungsID=" + BehID + " AND Datum= '" + datum + "'");

It worked perfectly witch Visual Studio 2003, but with Visual Studio 2008 I always get this Exception :( thanks for your help.

musefan

im suprised it worked in any version youor trying to compare a string to a dateTime which clearly is not the same type As the BehID is unique why use the datum value at all?

If only MySelf.Visible was more than just a getter... A person can produce over 5 times there own body weight in excrement each year... please re-read your questions before posting

Calin Tatar

Hi, Try to create a DateTime object from

datum

, to see if you have a valid data format in that string. Calin

Lodeclaw

You need to convert one or both sides of your statement so that they are both the same data type. A string type and a datetime type are incompatible, so find a way to collect the datetime information contained in your string explicitly and use DateTime.Parse to make it compatible.

Calin Tatar

Also, you should try to format your date as following: "#" + dt.Month + "/" + dt.Day + "/" + dt.Year + "#" Calin

der flori

I already tried to create a DateTime Object from

datum

and the Cast worked perfectly, but there occurs the same Exception when I edit the Code as follows:

DataRow[] VerlaufDatum = data1.Verlauf.Select("BehandlungsID=" + BehID + " AND Datum= '" + Convert.ToDateTime(datum) + "'");

I think it has something to do with the '=' Operator, but I don´t know what´s wrong with it :(

Calin Tatar

Try by formatting the date and pass this string: "#" + dt.Month + "/" + dt.Day + "/" + dt.Year + "#" Calin

der flori

hey, thanks a lot :))) that works fine and solves the problem perfectly!

Calin Tatar

I'm glad, no problem. Calin

Ennis Ray Lynch Jr

Ah, I love being reminded of Jet. Now we know where they DataSet team got there start.

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