DataSource error: "Cannot Bind to property or Column"

Question

I'm working on a database in C# when I hit the display button I get an error:

Error:
Cannot bind to the property or column LastName on the DataSource. Parameter name: dataMember

Code:

private void Display_Click(object sender, EventArgs e)
{
    Program.da2.SelectCommand = new SqlCommand("Select * From Customer", Program.cs);
    Program.ds2.Clear();
    Program.da2.Fill(Program.ds2);
    customerDG.DataSource = Program.ds2.Tables[0];

    Program.tblNamesBS2.DataSource = Program.ds.Tables[0];

    customerfirstname.DataBindings.Add(new Binding("Text", Program.tblNamesBS2, "FirstName"));
    customerlastname.DataBindings.Add(new Binding("Text", Program.tblNamesBS2, "LastName")); //Line Error occurs on.
}

Not sure what it means can anyone help, if I comment out the last two lines it will display properly.

Bayles

Have you checked that LastName is correctly typed? – Triturable

It means there is no column called LastName in the that table. – Disulfiram

Very odd, on my SQL server manager the colum name is indeed "LastName" just like what i have typed. if i just comment out the last line it works, FirstName is correct and i spelt LastName in the same manner. – Bayles

The DataSource of Program.tblNamesBS2 is Program.ds.Tables[0]. But you have filled the results to another Dataset Program.ds2. Is this correct? – Malmsey

I have 2 Data sets. Program.TblNamesBS is Program.ds.Tables[0]. and i also have Program.tblNamesBS2 is Program.ds2.Tables[0]. No 2 is used for my customer form and the orginal is used for my contact Form ive used the same method. – Bayles

Ahh ty Mohammad that fixed it. Should have been Program.ds2.Tables[0] – Bayles

Slight prob if i click display it loads the table, but if i click display once again i get this error msg, is there a way to prevent this.. This causes two bindings in the collection to bind to the same property. Parameter name: binding – Bayles

I think you will have to clear the bindings before adding new bindings. And khan is this a windows application? – Malmsey

Answer 1

it means your datatable is not finding column name LastName which is in your database..

in your case you filling your dataset with ds2..

 Program.da2.Fill(Program.ds2); 

and then you are binding your datasource to 'program' like this..

Program.tblNamesBS2.DataSource = Program.ds.Tables[0];  

it should like this..

Program.tblNamesBS2.DataSource = Program.ds2.Tables[0];  

because below line you are looking value from Program.tblNamesBS2 which is binded to 'ds' and that's why column are not ther in 'ds'.

 customerfirstname.DataBindings.Add(new Binding("Text", Program.tblNamesBS2, "FirstName"));    
  customerlastname.DataBindings.Add(new Binding("Text", Program.tblNamesBS2, "LastName"));

Otero

Why would this be? it can find FirstName, and LastName is spelt properly. – Bayles

Answer 2

You will also run into this error if you bind to a NULL object.

Journalism

Create a new instance of the object and bind to that. – Journalism

Answer 3

Another reason for this error is if the property you are binding to is private.

Utica

Answer 4

Yet another possible reason for this (if you bind to an object) is that you try to bind to a field, not a property.

Redtop

Thanks Michael. I just tripped over this. – Yoshi

Answer 5

I had the same problem and it was because the columns in both my tables had the same column names. For example:

1. My database name was Assets;
2. The first table name was Property and the second table name was Plants;
3. The first column names in both the tables were asset_number; It gave the error you describe above, but mine said asset_number.

Solution: I changed the column names in my table Plants to asset_number1 and then it had no problem. (I did have to delete all my old columns in Plants to redo the new columns.)

Kennedy

Answer 6

I run into the same problem where I have to change the name in the table but I haven't change column names in the data binding file. solution was changing the names by replacing the changed name.

Archegonium