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Cannot Cast Dbnull To String


converting to dbnull System.FormatException: Input String was not in a correct format. Have a look at the XSD for your dataset (or have a look at it in the DataSet designer). DataRow row = ds.Tables[0].Rows[0]; string value; if (row["fooColumn"] == DBNull.Value) { value = string.Empty; } else { value = Convert.ToString(row["fooColumn"]); } As Manu said, you can create a convert class with If a reviewer makes significant contributions to improving a paper, may he/she suggest becoming a coauthor?

If so: object obj; if((obj = c.spCartListSmall(Session.SessionID)) == DBNull.Value) lblBasket.Text = String.Empty; else lblBasket.Text = Convert.ToString(obj); Reply PeterLarsson None 0 Points 28 Posts Re: Convert 'System.DBNull' to type 'System.String' ? Not the answer you're looking for? I marked this property to be data bindable. well helps:public static object ReadNullIfDbNull(IDataReader reader, intcolumn){object value = reader.GetValue(column);return value == DbNull.Value ?

Unable To Cast Object Of Type 'system.dbnull' To Type 'system.string'. C#

If the WHERE does not match any row, you'll get a null, if the selected row has NULL in that column, the return value is System.DBNull. –Alexander May 27 '14 at And all my problem is with this data source control. Why is this C++ code faster than my hand-written assembly for testing the Collatz conjecture?

http://msdn.microsoft.com/en-us/library/Aa479341.aspx Reply Hapani Ankit... How can I convert that toa system.sting>ThanksRobert Dec 2 '06 #9 P: n/a Robert Bravery DAve, Thanks for this. Then you have your clean code as original version. Unable To Cast Object Of Type System Dbnull To Type System Byte Vb Net I changed one method signature and broke 25,000 other classes.

Privacy statement Dev Centers Windows Office More... The Value For Column In Table Is Dbnull C# General FAQ Ask a Question Bugs and Suggestions Article Help Forum Site Map Advertise with us About our Advertising Employment Opportunities About Us Ask a Question All Questions All Unanswered FAQ Is there something wrong in the method, or maybe you can put it returning String.Empty Reply NC01 All-Star 40650 Points 15353 Posts Re: Convert 'System.DBNull' to type 'System.String' ? How can I convert that to a system.sting Thanks Robert Dec 2 '06 #4 P: n/a Dave Sexton Hi Robert, When using a Typed DataSet you must check first if the

And I used SQLDataSource to bind the Byte[] BinData property. Dbnull In C# Example Cheers, Stefan Delmarco http://www.fotia.co.uk Hello Robert, From the code snippet it looks like you're using a strongly typed data set. Wait... Instead of the hard cast, call the object's .ToString() method.

The Value For Column In Table Is Dbnull C#

The 10'000 year skyscraper more hot questions question feed default about us tour help blog chat data legal privacy policy work here advertising info mobile contact us feedback Technology Life / How is it packed? Unable To Cast Object Of Type 'system.dbnull' To Type 'system.string'. C# Linux questions C# questions ASP.NET questions fabric questions SQL questions discussionsforums All Message Boards... Unable To Cast Object Of Type 'system.dbnull' To Type 'system.byte ' My best advice is this: For columns that can be null in the database, use nullable types.

But the return type is of system.dbnull. However, since you allow null values in your database table, if there is a null value in your resultant set, it will return DBNull.Value to your reader. Hello Robert, Just call ToString() on the value returned. Find the function given its Fourier series Creating a table with FIXED length column widths What is the total sum of the cardinalities of all subsets of a set? Cannot Implicitly Convert Type 'system.dbnull' To 'string'

share|improve this answer answered Aug 25 '08 at 20:45 Pascal Paradis 3,14352644 add a comment| up vote 1 down vote For some reason I've had problems with doing a check against string.Empty; , with accountNumber still being an object. Member 675 Points 533 Posts Re: Convert 'System.DBNull' to type 'System.String' ? http://txtbl.com/unable-to/cannot-convert-system-dbnull-to-string.html It's ever-so-slightly faster than casting though only in certain cases.

I bet that the "NullValue" property for the FirstName column is "(Throw)". Convert.tostring Dbnull The reasoning is that with non-nullable types, you are going to have to resort to "magic numbers" to represent null. For example setting a value to an empty string as opposed to a value just never being set. –Mykroft Oct 24 '08 at 17:44 add a comment| up vote 0 down

Perhaps, maybe if you have a class that manages the assignment of the data source I can see something in a different light.

How can I declare independence from the United States and start my own micro nation? Browse more C# / C Sharp Questions on Bytes Question stats viewed: 30138 replies: 9 date asked: Dec 2 '06 Follow this discussion BYTES.COM 2016 Formerly "TheScripts.com" from 2005-2008 About String.Empty; –Chaitanya Jan 19 '10 at 6:34 add a comment| up vote 3 down vote There is another way to workaround this issue. System.dbnull Check See more: ASP.NET MySQL MVC Hello Guys, morning, i got stuck with of the freaking problem i.e.

Will try it later tonight! string.Empty; share|improve this answer answered May 15 '09 at 20:34 Nathan Koop 13.6k1966111 +1 You beat me to it. :( –dss539 May 15 '09 at 20:38 -1: I mean, my code has following definition of the byte[] type property, 1 private byte[] binData; 2 3 [Bindable(true)] 4 [Category("Data Input fields")] 5 [Localizable(true)] 6 So why should you do the same?

public byte[] BinData { get { return this._bBinData; } set { if(value.Equals(DBNull.Value) || value == null) { // set to initialized byte array or byte[] representation of a empty string like