ListBox.ObjectCollection.IndexOf Method (Object)


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Returns the index within the collection of the specified item.

Namespace:   System.Windows.Forms
Assembly:  System.Windows.Forms (in System.Windows.Forms.dll)

public int IndexOf(
	object value


Type: System.Object

An object representing the item to locate in the collection.

Return Value

Type: System.Int32

The zero-based index where the item is located within the collection; otherwise, negative one (-1).

Exception Condition

The value parameter is null.

The IndexOf method enables you to determine where an item is located within the collection. To determine whether an item is located within the collection before calling this method, use the Contains method.

.NET Framework
Available since 1.1
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