Untitled

using System.Collections;
using System.Collections.Generic;
using UnityEditor.Build.Content;
using UnityEngine;

public class PlayerDragAndDrop : MonoBehaviour
{

    public Camera cam;
    public Collider draggeableArea;

    private GameObject draggedObject;

    private void Start()
    {
        draggeableArea = GameObject.Find("Draggeable Area").GetComponent<Collider>();
    }

    void Update()
    {
        
        if  (Input.GetMouseButtonDown(0) && draggedObject == null) 
        {
            SelectDraggeableObject();   
        }

        if (Input.GetMouseButton(0) && draggedObject != null) 
        {
            MoveDraggedObject();    
        }

        if (Input.GetMouseButtonUp(0) && draggedObject != null)
        {
            DropDraggedObject();
        }

    }

    void SelectDraggeableObject()
    {

        Ray ray = cam.ScreenPointToRay(Input.mousePosition);
        RaycastHit hit;
        Debug.DrawRay(ray.origin, ray.direction * 100, Color.red);

        if (Physics.Raycast(ray, out hit, 100))
        {
            if (hit.collider.TryGetComponent (out DraggeablePlayer draggeablePlayer))
            {
                draggedObject = draggeablePlayer.gameObject;
            }
        }

    }

    void MoveDraggedObject()
    {

        Vector2 cameraToWorldPoint = cam.ScreenToWorldPoint(new Vector2(Input.mousePosition.x, Input.mousePosition.y));
        Vector3 transformPoint = new Vector3(cameraToWorldPoint.x, cameraToWorldPoint.y, draggedObject.transform.position.z);

        if (draggeableArea.bounds.Contains(transformPoint))
        {

            draggedObject.transform.position = transformPoint;

        }
    }

    void DropDraggedObject()
    {
        draggedObject = null;
    }

}