How can i move a Keyframe on an Animation Curve with overwriting the key on the target time?

Hi yale3d, I t$$anonymous$$nk AnimationCurve.MoveKey will not overwrite existing key at the target time, so you need to remove that existing key first before moving the selected key.

Or maybe you can take a look at the following extension method, MoveKeyOverwrite.

 using UnityEngine;
 
 public class TestAnimCurve : MonoBehaviour
 {
     public AnimationCurve curve = new AnimationCurve(
         new Keyframe(0, 0),
         new Keyframe(1, 1));
 
     private void Update()
     {
         if (Input.GetKeyDown(KeyCode.Z))
         {
             // Move key0 to time:1
 
             int selectedKeyIndex = 0;
             Keyframe selectedKey = curve.keys[selectedKeyIndex];
             selectedKey.time = 1;
 
             curve.MoveKeyOverwrite(selectedKeyIndex, selectedKey);
         }
     }
 }
 
 
 public static class AnimationCurveExtensions
 { 
     public static void MoveKeyOverwrite(t$$anonymous$$s AnimationCurve curve, int index, Keyframe key)
     {
         if (curve.keys != null && curve.keys.Length > 0)
         {
             for (int i = 0; i < curve.keys.Length; i++)
             {
                 if (Mathf.Approximately(curve.keys[i].time, key.time))
                 {
                     curve.RemoveKey(i);
                 }
             }
         }
 
         curve.MoveKey(index, key);
     }
 }