JSFiddle - React, Tailwind, and code Playground

JavaScript

var array1 = ['12345', '78273', '34784'],
        array2 = ['JJJJJ', 'ABCDEF', 'FFDDFF'];
    
    Array.prototype.containsSubString = function( text ){
        for ( var i in this )
        {
            if ( this[i].toString().indexOf( text ) != -1 )
                return i;
        }
        return -1;
    }
    
    if( array1.containsSubString( 234 ) !== -1) 
    {
        alert("Found in Array1!");
    }
    
    if( array2.containsSubString( 'DD' ) !== -1) 
    {
        alert("Found! in Array2");
    }

    console.log( array1.containsSubString( 'DD' ) );