DataView Rowfilter表达式C＃

Question

I am having a dataTable in which one of the columns is of a specific type of object say typeOf(A) - A being my custom class. The class A is having a text property and other properties like bool. From user or external code I get only the text value to be used in RowFilter for Filtering, in the below example I will get "cat" as my filter to be used. Using this how to create the RowFilterExpression?

class A
{
   public string Text{get;set;}
   public bool isReadonly {get;set;}
} 

DataTable table = new DataTable();
table.Columns.Add("col1", typeOf(A));
table.Rows.Add(new A{Text = "cat", isReadOnly = true,})
table.Rows.Add(new A{Text = "dog", isReadOnly = false,})

string filter = "cat";

DataView dataView = new DataView(table);
dataView.RowFilter = "[col1]='"+filter+"'";

The above expression doesnot work because it tries to match it to the object in cell. how to filter out the 1st row alone using this filter expression?

Any help is appreciated.

Answer 1

Try overriding ToString method in your object and then your current filtering code should work

class A
{
   public string Text{get;set;}
   public bool isReadonly {get;set;}

   public override string ToString()
   {
      return this.Text;
   }
} 

Answer 2

overriding object ToString method like this :

class A
{
    public string Text { get; set; }
    public bool isReadonly { get; set; }

    public override string ToString()
    {
        return this.Text;
    }
}

and you can use :

dataView.RowFilter = string.Format("Convert([col1], 'System.String') = '{0}'", filter);