Re: Newline in constant error - C# Discussion Boards

Newline in constant error

21-Jun-04 11:40

I haven't run into this, but if you want to make sure your app is going to work on all of your platforms, Test, Test, Test, Test, and Test some more, until YOU'RE happy with the functionality. Then hand it to a couple of beta testers and see if THEY'RE happy with the product on the platforms your suspicious of.

RageInTheMachine9532
"...a pungent, ghastly, stinky piece of cheese!" -- The Roaming Gnome

vcorn21-Jun-04 8:05

21-Jun-04 8:05

hi, anyone know about that kind of error?
Thanks

Dave Kreskowiak21-Jun-04 8:17

21-Jun-04 8:17

It would help if you posted the code where the error occurs!

RageInTheMachine9532
"...a pungent, ghastly, stinky piece of cheese!" -- The Roaming Gnome

vcorn21-Jun-04 8:53

21-Jun-04 8:53

Thanks David,
i close the Visual Studio and reopen,
everything's just fine then,
sounds weird though..
Thanks

But i have another question, i wanna apply column style to one of the columns in my table, i wanna hide one column but setting its width to zero, i have five datacolumn object, but i only have one gridcolumnstyle with mapping name set to one of the column name i wanna hide.
but the style doesn't apply, the column is not hidden.
how am i goin to hide it?

Dave Kreskowiak21-Jun-04 9:04

21-Jun-04 9:04

You hide the column by setting it's width to 0, but since you haven't supplied any code, I can't tell you what your doing wrong. So, here's an example:

private void HideColumnOfDataSet()
{
    System.Data.DataTable points = new System.Data.DataTable("Points");
    points.Columns.Add(new DataColumn("X", typeof(int)));
    points.Columns.Add(new DataColumn("Y", typeof(int)));
    points.Rows.Add(new object[]{1, 2});
    points.Rows.Add(new object[]{3, 5});
    dataGrid1.DataSource = points;
 
    DataGridTableStyle tableStyle = new DataGridTableStyle();
    tableStyle.MappingName = "Points";
    dataGrid1.TableStyles.Add(tableStyle);
    dataGrid1.TableStyles["Points"].GridColumnStyles["X"].Width = 0;
}

RageInTheMachine9532
"...a pungent, ghastly, stinky piece of cheese!" -- The Roaming Gnome

vcorn21-Jun-04 9:19

21-Jun-04 9:19

i get null reference exception in this line
this.dataGrid1.TableStyles["Students"].GridColumnStyles["Password"].Width = 0;
how?

Dave Kreskowiak21-Jun-04 9:27

21-Jun-04 9:27

I can't tell without seeing the rest of your code in that block. Most likely, you're missing a 'new' somewhere.

RageInTheMachine9532
"...a pungent, ghastly, stinky piece of cheese!" -- The Roaming Gnome

vcorn21-Jun-04 9:31

21-Jun-04 9:31

Thanks Dave,
found it,
i did it inside the initialize component(using designer)
and indeed the designer define the table style before adding column.
i replace the order, add column first, then it's fine.
Thanks Smile | :)

Heath Stewart21-Jun-04 9:54

21-Jun-04 9:54

Accessing indexes requires that an object at that index (or with that index keyword, like the table style or column style name above) exists. If it doesn't, null is returned from the index property. When you try to call a method or access a property on null, you get a NullReferenceException.

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enumerating groups a user belongs to using WinNT://

the last free name21-Jun-04 21:37

the last free name

21-Jun-04 21:37

I sometimes see it in a perfectly valid line of code. I simply cut and re-paste the line and the compiler is then happy!

inyoursadachine21-Jun-04 6:58

inyoursadachine

21-Jun-04 6:58

Hi,
How does one enumerate the groups a user belongs to using the WinNT:// provider (not LDAP) ??

TIA,
Matt

Re: enumerating groups a user belongs to using WinNT://

Dave Kreskowiak21-Jun-04 8:12

21-Jun-04 8:12

Well, in VBScript, it looks something like this:

strComputer = "."   ' Use a '.' to denote the local machine.
Set colGroups = GetObject("WinNT://" & strComputer & "")
colGroups.Filter = Array("group")
For Each objGroup In colGroups
    For Each objUser in objGroup.Members
        If objUser.name = "username" Then
            Wscript.Echo objGroup.Name
        End If
    Next
Next

You go through each group on the machine and check to see if the username exists in that group.

RageInTheMachine9532
"...a pungent, ghastly, stinky piece of cheese!" -- The Roaming Gnome

serializing in c#.net

fatidarya21-Jun-04 6:18

21-Jun-04 6:18

i want serialize and deserialize textbox properties for example font and backcolor,...
please help me and tell me what i do?
thanks

Heath Stewart21-Jun-04 6:38

21-Jun-04 6:38

Read the XmlSerializer class documentation in the .NET Framework SDK. It includes a sample.

XML Serialization will, by default, serialize any public property or field, so serializing those properties is easy:

TextWriter writer = new XmlTextWriter("file.xml",
  System.Text.Encoding.UTF8);
XmlSerializer serializer = new XmlSerializer(textBox1.GetType());
serializer.Serialize(writer, textBox1);

See the documentation for more details.

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fatidarya21-Jun-04 21:31

21-Jun-04 21:31

my code is
this is serialize of textbox:
XmlWriter xw = new XmlTextWriter(fs, System.Text.Encoding.ASCII);
xw.WriteStartElement("Form");
xw.WriteAttributeString("X", theText.Left.ToString());
xw.WriteAttributeString("Y", theText.Top.ToString());
xw.WriteAttributeString("Width", theText.Width.ToString());
xw.WriteAttributeString("Height", theText.Height.ToString());
xw.WriteAttributeString("Value", theText.Text);
xw.WriteAttributeString("Font", theText.Font.Tostring());
xw.WriteAttributeString("Backcolor", theText.Backcolor.Tostring());
xw.WriteEndElement();
XmlNodeReader reader = new XmlNodeReader(doc);reader.value is string but textbox.font or backcolor is Syste.Drawing
please tell me what i do? Confused | :confused:

thanks.

Re:thanks &deserializing in c#.net

thomasa21-Jun-04 22:42

thomasa

21-Jun-04 22:42

I'm not shore about the Font but with the Backcolor you can:
xw.WriteAttributeString("Backcolor", theText.BackColor.ToArgb().ToString());

and read it inn with
theText.BackColor = Color.FromArgb(Convert.ToInt32(reader.Value));

the font you might have to use

theText.Font.Name.ToString()

Hope it helps
Thomas

fatidarya22-Jun-04 0:43

22-Jun-04 0:43

thanks for your help
but i should deserialize font and alignment of my textbox with reader.value ,too
please tell me what i do?
thanks.

Heath Stewart22-Jun-04 2:38

22-Jun-04 2:38

You should be using TypeConverters for the whole thing, otherwise use ToString. Many classes can't be reconstituted from their ToString representations. If you use XmlSerializer as I mentioned, this is all done for you. But, if you insist on doing things the hard way, you can get a TypeConverter reference for each type using something like this:

TypeConverter converter = TypeDescriptor.GetConverter(theText.Left);
xw.WriteAttributeString("X", converter.ConvertToString(theText.Left));
converter = TypeDescriptor.GetConverter(theText.Top);
xw.WriteAttributeString("Y", converter.ConvertToString(theText.Top));
// ...
xw.WriteEndElement();

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fatidarya22-Jun-04 3:00

22-Jun-04 3:00

the serialize code:
xw.WriteAttributeString("Font",theText.Font.Name.ToString());
and it is deserialize code,i use convector but it dosent work properly.
FontConverter ff=new FontConverter();
theTextBox.Font=(System.Drawing.Font )ff.ConvertFromString(reader.Value );
what i do?
thanks.

Heath Stewart22-Jun-04 4:07

22-Jun-04 4:07

You don't instantiate the FontConverter itself, which is documented if you bother to read it. Always use TypeDescriptor.GetConverter.

And instead of saying "doesn't work properly" - which is has in my experience - you might want to be more specific about what's not working, since I can't really help if I don't know what the problem you're having is.

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fatidarya22-Jun-04 19:12

22-Jun-04 19:12

thanks for reply
i use from TypeConvector in my code but c# dosent know it.
my serialize or save code is:
xw.WriteStartElement("TextBox");
xw.WriteAttributeString("X", theText.Left.ToString());
xw.WriteAttributeString("Y", theText.Top.ToString());
xw.WriteAttributeString("Width",c.Width.ToString());
xw.WriteAttributeString("Height",c.Height.ToString()); xw.WriteAttributeString("Value", c.Text);
TypeConverter converter = TypeDescriptor.GetConverter(theText.Font); xw.WriteAttributeString("Font", converter.ConvertToString(theText.Font))
xw.WriteAttributeString("TextAlign",theText.TextAlign.ToString());
xw.WriteAttributeString("Backcolor",c.BackColor.ToArgb().ToString());
xw.WriteAttributeString("Forecolor",c.ForeColor.ToArgb().ToString());
xw.WriteEndElement();
and my deserialize or read code is:
for (int i = 0; i < reader.AttributeCount; i++)
{
reader.MoveToAttribute(i); switch(reader.Name)
{
case "X":
theTextBox.SetBounds(Convert.ToInt32(reader.Value),
theTextBox.Top, theTextBox.Width, theTextBox.Height);
break; case "Y": theTextBox.SetBounds(theTextBox.Left,
Convert.ToInt32(reader.Value), theTextBox.Width,theTextBox.Height); break;
.. case "Font": TypeConverter ff = TypeDescriptor.GetConverter(reader.value);
theTextBox.Font=(System.Drawing.Font)ff.ConvertFromString (reader.Value );
break;
case "Backcolor":
theTextBox.BackColor= Color.FromArgb(Convert.ToInt32(reader.Value));
break;
please tell me,what i do for my deserialize code?

Heath Stewart22-Jun-04 19:19