> For the complete documentation index, see [llms.txt](https://boxlang.ortusbooks.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://boxlang.ortusbooks.com/boxlang-language/reference/built-in-functions/array/arrayindexexists.md). # ArrayIndexExists Returns whether there exists an item in the array at the selected index. ## Method Signature ``` ArrayIndexExists(array=[array], index=[any]) ``` ### Arguments | Argument | Type | Required | Description | Default | | -------- | ------- | -------- | ------------------------- | ------- | | `array` | `array` | `true` | The array to be searched. | | | `index` | `any` | `true` | The index to check. | | ## Examples ### Simple example To check an array element is define or not [Run Example](https://try.boxlang.io/?code=eJwrzs9NdSwqSqxUsFWIVuDiNNTh4jQCYmMgNgFiU65Ya67yosySVP%2FSkoLSEg2FRJBqz2KX1LTMvNQUDYVimAk6CsYKmgqa1lwAtkgXRQ%3D%3D) ```java someArray = [ 1, 2, 3, 4, 5 ]; writeOutput( arrayIsDefined( someArray, 3 ) ); ``` Result: Yes ### Simple example To check an array element is define or not [Run Example](https://try.boxlang.io/?code=eJwrzs9NdSwqSqxUsFWIVuDiNNTh4jQCYmMgNgFiU65Ya67yosySVP%2FSkoLSEg2FRJBqz2KX1LTMvNQUDYVimAk6CmYKmgqa1lwAtl0XSA%3D%3D) ```java someArray = [ 1, 2, 3, 4, 5 ]; writeOutput( arrayIsDefined( someArray, 6 ) ); ``` Result: false ### Simple example with two dimensional array To check an array element is define or not [Run Example](https://try.boxlang.io/?code=eJxzyywqLnEsKkqsVLBViFbg4jTU4eI0AmJjrlhrruLU5Py8FLg0UBYkbQiSNwQrSM7PTcrMS4WpSATRfqnlGgpGCprWXGCuY0FBal6KhgKyUh2FNIS9%2BBUiOwGosrwosyTVv7SkoLREA2KdZ7FLahpQPYZOYwVNkA4AntpGyg%3D%3D) ```java FirstArray = [ 1, 2, 3 ]; secondArray = [ 11, 12, 13 ]; combineArray = arrayNew( 2 ); arrayAppend( combineArray, firstArray ); arrayAppend( combineArray, secondArray ); writeOutput( arrayIsDefined( combineArray, 3 ) ); ``` Result: No ### Simple example with two dimensional array To check an array element is define or not [Run Example](https://try.boxlang.io/?code=eJxzyywqLnEsKkqsVLBViFbg4jTU4eI0AmJjrlhrruLU5Py8FLg0UBYkbQiSNwQrSM7PTcrMS4WpSATRfqnlGgpGCprWXGCuY0FBal6KhgKyUh2FNIS9%2BBUiOwGosrwosyTVv7SkoLREA2KdZ7FLahpQPYZOoBNAOgCe00bJ) ```java FirstArray = [ 1, 2, 3 ]; secondArray = [ 11, 12, 13 ]; combineArray = arrayNew( 2 ); arrayAppend( combineArray, firstArray ); arrayAppend( combineArray, secondArray ); writeOutput( arrayIsDefined( combineArray, 2 ) ); ``` Result: true ### Additional Examples [Run Example](https://try.boxlang.io/?code=eJxFjcEKwjAMhs%2FmKcJOGwwn7Dg8CF58BvGQuVSCa1eyFvHt7apYcsgHf74%2FRqOEkyq98YhXhF1F3s9ctYme8pIMI7k0GRcl9%2FjGNtFSDuE2wBStr5G2ust6ZiOOpxrN%2F0eLPTbYDNh1GDQypG3ZjqxoorsHWdyvozh7KU39Ieuw%2BYbmleEDVd85ZQ%3D%3D) ```java fruitArray = [ "apple", "kiwi", "banana", "orange", "mango", "kiwi" ]; dump( arrayIsDefined( fruitArray, 3 ) ); // true // member function dump( fruitArray.isDefined( 30 ) ); // false ``` ## Related * [ArrayAppend](/boxlang-language/reference/built-in-functions/array/arrayappend.md) * [ArrayAvg](/boxlang-language/reference/built-in-functions/array/arrayavg.md) * [ArrayChunk](/boxlang-language/reference/built-in-functions/array/arraychunk.md) * [ArrayClear](/boxlang-language/reference/built-in-functions/array/arrayclear.md) * [ArrayContains](/boxlang-language/reference/built-in-functions/array/arraycontains.md) * [ArrayContainsNoCase](/boxlang-language/reference/built-in-functions/array/arraycontainsnocase.md) * [ArrayDelete](/boxlang-language/reference/built-in-functions/array/arraydelete.md) * [ArrayDeleteAt](/boxlang-language/reference/built-in-functions/array/arraydeleteat.md) * [ArrayDeleteNoCase](/boxlang-language/reference/built-in-functions/array/arraydeletenocase.md) * [ArrayEach](/boxlang-language/reference/built-in-functions/array/arrayeach.md) * [ArrayEvery](/boxlang-language/reference/built-in-functions/array/arrayevery.md) * [ArrayFilter](/boxlang-language/reference/built-in-functions/array/arrayfilter.md) * [ArrayFind](/boxlang-language/reference/built-in-functions/array/arrayfind.md) * [ArrayFindAll](/boxlang-language/reference/built-in-functions/array/arrayfindall.md) * [ArrayFindAllNoCase](/boxlang-language/reference/built-in-functions/array/arrayfindallnocase.md) * [ArrayFindFirst](/boxlang-language/reference/built-in-functions/array/arrayfindfirst.md) * [ArrayFindNoCase](/boxlang-language/reference/built-in-functions/array/arrayfindnocase.md) * [ArrayFirst](/boxlang-language/reference/built-in-functions/array/arrayfirst.md) * [ArrayFlatMap](/boxlang-language/reference/built-in-functions/array/arrayflatmap.md) * [ArrayFlatten](/boxlang-language/reference/built-in-functions/array/arrayflatten.md) * [ArrayGetMetadata](/boxlang-language/reference/built-in-functions/array/arraygetmetadata.md) * [ArrayGroupBy](/boxlang-language/reference/built-in-functions/array/arraygroupby.md) * [ArrayInsertAt](/boxlang-language/reference/built-in-functions/array/arrayinsertat.md) * [ArrayIsDefined](/boxlang-language/reference/built-in-functions/array/arrayisdefined.md) * [ArrayLast](/boxlang-language/reference/built-in-functions/array/arraylast.md) * [ArrayMap](/boxlang-language/reference/built-in-functions/array/arraymap.md) * [ArrayMax](/boxlang-language/reference/built-in-functions/array/arraymax.md) * [ArrayMedian](/boxlang-language/reference/built-in-functions/array/arraymedian.md) * [ArrayMerge](/boxlang-language/reference/built-in-functions/array/arraymerge.md) * [ArrayMid](/boxlang-language/reference/built-in-functions/array/arraymid.md) * [ArrayMin](/boxlang-language/reference/built-in-functions/array/arraymin.md) * [ArrayNew](/boxlang-language/reference/built-in-functions/array/arraynew.md) * [ArrayNone](/boxlang-language/reference/built-in-functions/array/arraynone.md) * [ArrayPop](/boxlang-language/reference/built-in-functions/array/arraypop.md) * [ArrayPrepend](/boxlang-language/reference/built-in-functions/array/arrayprepend.md) * [ArrayPush](/boxlang-language/reference/built-in-functions/array/arraypush.md) * [ArrayRange](/boxlang-language/reference/built-in-functions/array/arrayrange.md) * [ArrayReduce](/boxlang-language/reference/built-in-functions/array/arrayreduce.md) * [ArrayReduceRight](/boxlang-language/reference/built-in-functions/array/arrayreduceright.md) * [ArrayReject](/boxlang-language/reference/built-in-functions/array/arrayreject.md) * [ArrayResize](/boxlang-language/reference/built-in-functions/array/arrayresize.md) * [ArrayReverse](/boxlang-language/reference/built-in-functions/array/arrayreverse.md) * [ArraySet](/boxlang-language/reference/built-in-functions/array/arrayset.md) * [ArrayShift](/boxlang-language/reference/built-in-functions/array/arrayshift.md) * [ArraySlice](/boxlang-language/reference/built-in-functions/array/arrayslice.md) * [ArraySome](/boxlang-language/reference/built-in-functions/array/arraysome.md) * [ArraySort](/boxlang-language/reference/built-in-functions/array/arraysort.md) * [ArraySplice](/boxlang-language/reference/built-in-functions/array/arraysplice.md) * [ArraySum](/boxlang-language/reference/built-in-functions/array/arraysum.md) * [ArraySwap](/boxlang-language/reference/built-in-functions/array/arrayswap.md) * [ArrayToList](/boxlang-language/reference/built-in-functions/array/arraytolist.md) * [ArrayToStruct](/boxlang-language/reference/built-in-functions/array/arraytostruct.md) * [ArrayTranspose](/boxlang-language/reference/built-in-functions/array/arraytranspose.md) * [ArrayUnique](/boxlang-language/reference/built-in-functions/array/arrayunique.md) * [ArrayUnshift](/boxlang-language/reference/built-in-functions/array/arrayunshift.md) * [ArrayZip](/boxlang-language/reference/built-in-functions/array/arrayzip.md) --- # Agent Instructions This documentation is published with GitBook. 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