How to hide column of DataGridView when using cust

问题:

I have a small app in c#, it has a DataGridView that gets filled using:

grid.DataSource = MyDatasource array;

MyClass hold the structure for the columns, it looks something like this:

class MyDatasource
{
    private string column1;        
    private string column2;

    public MyDatasource(string arg1, string arg2)
    {
        this.column1 = arg1;
        this.column2 = arg2;
    }

    public string column1
    {
        get
        {
            return this.column1;
        }
        set
        {
            this.column1 = value;
        }
    }

    public string column2
    {
        get
        {
            return this.column2;
        }
        set
        {
            this.column1 = value;
        }
    }
}

Everything works fine and the DataGridView gets populated with the correct data, but now I want to hide the column2. I tried adding [Browsable(false)] above the column declaration, that will hide it, but I also need to access the column value from code, and when I use [Browsable(false)] and try to read the content it acts like if the column doesn't exist. If I don't use it I can read the column without problem but it's visible in the DataGridView.

How could I hide the column but still be able to read its content from code?

回答1:

In some cases, it might be a bad idea to first add the column to the DataGridView and then hide it.

I for example have a class that has an NHibernate proxy for an Image property for company logos. If I accessed that property (e.g. by calling its ToString method to show that in a DataGridView), it would download the image from the SQL server. If I had a list of Company objects and used that as the dataSource of the DataGridView like that, then (I suspect) it would download ALL the logos BEFORE I could hide the column.

To prevent this, I used the custom attribute

 [System.ComponentModel.Browsable(false)]

on the image property, so that the DataGridView ignores the property (doesn't create the column and doesn't call the ToString methods).

 public class Company
 {
     ...
     [System.ComponentModel.Browsable(false)]
     virtual public MyImageClass Logo { get; set;}

回答2:

You have to hide the column at the grid view control rather than at the data source. Hiding it at the data source it will not render to the grid view at all, therefore you won't be able to access the value in the grid view. Doing it the way you're suggesting, you would have to access the column value through the data source as opposed to the grid view.

To hide the column on the grid view control, you can use code like this:

dataGridView1.Columns[0].Visible = false;

To access the column from the data source, you could try something like this:

object colValue = ((DataTable)dataGridView.DataSource).Rows[dataSetIndex]["ColumnName"];

回答3:

I have noticed that if utilised progrmmatically it renders incomplete (entire form simply doesn't "paint" anything) if used before panel1.Controls.Add(dataGridView); then dataGridView.Columns["ID"].Visible = false; will break the entire form and make it blank, so to get round that set this AFTER EG:

 panel1.Controls.Add(dataGridView);
 dataGridView.Columns["ID"].Visible = false; 
 //works

 dataGridView.Columns["ID"].Visible = false; 
 panel1.Controls.Add(dataGridView);
 //fails miserably

回答4:

I"m not sure if its too late, but the problem is that, you cannot set the columns in design mode if you are binding at runtime. So if you are binding at runtime, go ahead and remove the columns from the design mode and do it pragmatically

ex..

     if (dt.Rows.Count > 0)
    {
        dataGridViewProjects.DataSource = dt;
        dataGridViewProjects.Columns["Title"].Width = 300;
        dataGridViewProjects.Columns["ID"].Visible = false;
    }

回答5:

Set that particular column's Visible property = false

dataGridView[ColumnName or Index].Visible = false;

Edit sorry missed the Columns Property dataGridView.Columns[ColumnName or Index].Visible = false;

回答6:

I had the same problem

Here is the Solution that might work for you. It worked for me

    GridView1.DataBind();
if (GridView1.Columns.Count > 0)
    GridView1.Columns[0].Visible = false;
else
{
    GridView1.HeaderRow.Cells[0].Visible = false;
    foreach (GridViewRow gvr in GridView1.Rows)
    {
        gvr.Cells[0].Visible = false;
    }
}

回答7:

Just set DataGridView.AutoGenerateColumns = false;

You need click on the arrow on top right corner (in datagridview) to add columns, and in DataPropertyName you need to put a name of your property in your class.

Then, after you defined your columns in datagridview, you can set datagridview.datasource = myClassViewModel.