- 1 year ago
ListBox.DisplayMember and Internal Properties
In Windows Forms, the DisplayMember
property of a ListBox
control allows you to specify the name of the property or column that should be displayed in the list. However, the DisplayMember
property requires a public property or column name that exists in the data source or the bound objects.
If you want to display a value that is not a public property or column, you can use a workaround by creating a wrapper class or using the ToString
method of the objects in the list. Here's an example:
Create a wrapper class that contains the internal value you want to display:
csharppublic class MyWrapperClass
{
public string InternalValue { get; set; }
public override string ToString()
{
return InternalValue;
}
}
Use the wrapper class as the data source for the
ListBox
control:csharpvar list = new List<MyWrapperClass>
{
new MyWrapperClass { InternalValue = "Value 1" },
new MyWrapperClass { InternalValue = "Value 2" },
new MyWrapperClass { InternalValue = "Value 3" }
};
listBox1.DataSource = list;
listBox1.DisplayMember = "InternalValue";
In this example, the ToString
method of the MyWrapperClass
is overridden to return the internal value, which will be displayed in the ListBox
control. By setting the DisplayMember
property to "InternalValue"
, the ListBox
control will use the InternalValue
property as the display value.
Note that this approach works if you have control over the objects in the list and can modify them or create wrapper classes. If the internal properties are not accessible or you cannot modify the objects, you may need to consider other approaches or alternative controls that provide more flexibility in displaying custom values.