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Array.exists(Int32) Method

Definition

Determines whether a particular array element is valid.

public:
 bool exists(int _index);
public bool exists (int _index);
member this.exists : int -> bool
Public Function exists (_index As Integer) As Boolean

Parameters

_index
Int32

The array element to test.

Returns

true if the array element that is pointed to by the index is valid; otherwise, false.

Remarks

The following example uses the exists method to test whether various elements in an array are valid.

{ 
    array a = new array(types::Integer); 
    a.value(1, 23); 
    print a.value(1); 
    pause; 
    if (a.exists(7)) // No, only element 1 is initialized 
    { 
        print a.value(7); 
    } 
    else  
    { 
        print "Value does not exist"; 
    } 
    pause; 
    //Array positions 2 to 9 padded with default values 
    a.value(10, 55); 
    if (a.exists(7)) // Yes, elements 1..10 now initialized 
    { 
        print a.value(7); 
    } 
    else  
    { 
        print "Value does not exist"; 
    } 
    pause; 
}

Applies to