Not able to add instance to array after adding in mapping in one function

Question

function addCropDetails //only farmer can call ( uint _cropType, //string memory _cropName, uint _quantity, string memory _location ) public { require ( owner != msg.sender , "owner cant add crop details" ); //u r not registered yet require (farmers[msg.sender].isRegistered == true, "You are not registered yet or you are not farmer"); require ( allPricesSet==true , "gov isnt initialized prices yet" ); require ( setProfitPercent == true , "gov isnt initialized profit rates yet" ); require ( _cropType < arraySize && _cropType >= 0 , "invalid crop type");

    uint cropPr = cropTypes[_cropType]; //fetched cropPrice by cropType (by gov)
    
    cropCounter++;
    Crop memory crop ;
    crop.cropId=cropCounter;
    //adding crop type to cropType
    crop.cropType = _cropType;        
    crop.farmer_quantity=_quantity;
    crop.location=_location;
    crop.farmerAddrs = payable(msg.sender);
    crop.cropPrice = cropPr;
    crop.isAdded=true;
    crops[cropCounter] = crop;      //here i passed instance to mapping
    

//in below lines i tried to add instance to array in many ways but not even one is working //function is working only after commenting this.

    //fCropArray[cropCounter] = crops[cropCounter];    
    //fCropArray[cropCounter]=crop;
    //addCropToArray(crops[cropCounter]);
    
    emit cropAdded();
}

Answer 1

cropCounter++;
...
crops[cropCounter] = crop;

If this is a dynamic array and you are attempting to implicitly extend it (as I assume is the case), then you are stepping out of bounds. It fails because cropCounter is not lessThanOrEqual to crops.length.

Try

crops.push(crop);

That explicitly appends an element to the end and increases the array length.

Hope it helps.