Array.indexOf Method
Returns the index of the first occurance a value in the Array.
object.indexOf (value[, startIndex])
Arguments
- object
- Required. Always the name of an Array object.
- value
- Required. The value to search for within the Array object.
- startIndex
- Optional. Integer value specifying the index to begin searching within the Array object. If omitted, searching starts at the beginning of the Array.
Return Value
The Array.indexOf method returns the following values:
| If |
Array.indexOf returns |
| value is the value of an element of object whose
index is between startIndex and object.length |
the index of the first element that contains exactly value |
| value is not the value of an element of object whose
index is between startIndex and object.length |
-1 |
Remarks
The following example illustrates the use of the Array.indexOf method.
var a = new Array("a", "c", "b", "d", "b");
Console.Writeln(a.indexOf("k")); // returns -1
Console.Writeln(a.indexOf("b")); // returns 2
Console.Writeln(a.indexOf("b", 3)); // returns 4
Console.Writeln(a.indexOf("c", 3)); // returns -1
Requirements