好久没有写东西了，因为最近忙，做一些项目上具体的功能。由于偶尔还是要拼一下UI，感觉对齐还是一个问题。虽然在以前写过一个一键对齐父节点的东西，可还是不够用，Unity中没有其他工具一样的辅助线。。。so,如果要让两个UI项以某种方式对齐排列，自己手动摆毛事总有那么一点点误差，除非你改坐标。我的功能是这样的：

支持 缩放、锚点、中心点 不同，全部一键搞定。

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

/// <summary>
/// Introduction: GUIAlignOthers
/// Author:     Cheng
/// Time: 
/// </summary>
public class GUIAlignOthers :Editor
{

    [MenuItem("GameObject/UI/Align/Top")]
    static void AlignTop()
    {
        Align(1);
    }
    [MenuItem("GameObject/UI/Align/Left")]
    static void AlignLeft()
    {
        Align(2);
    }
    [MenuItem("GameObject/UI/Align/Right")]
    static void AlignRight()
    {
        Align(3);
    }
    [MenuItem("GameObject/UI/Align/Bottom")]
    static void AlignBottom()
    {
        Align(4);
    }
    [MenuItem("GameObject/UI/Align/Horizontal")]
    static void AlignHorizontal()
    {
        Align(5);
    }
    [MenuItem("GameObject/UI/Align/Vertical")]
    static void AlignVertical()
    {
        Align(6);
    }

    static void Align(int type)
    {
        List<RectTransform> rects = new List<RectTransform>();
        GameObject[] objects = Selection.gameObjects;
        foreach (var obj in objects)
        {
            RectTransform rect = obj.GetComponent<RectTransform>();
            if (rect != null)
                rects.Add(rect);
        }

        if (rects.Count > 1)
        {
            Align(type, rects);
        }
    }



    static void Align(int type, List<RectTransform> rects)
    {
        RectTransform tenplate = rects[0];
        float w = tenplate.sizeDelta.x * tenplate.lossyScale.x;//消除缩放影响
        float h = tenplate.sizeDelta.y * tenplate.localScale.y;

        float x = tenplate.position.x - tenplate.pivot.x * w; //消除中心点并非pivot非（0.5，0.5）影响
        float y = tenplate.position.y - tenplate.pivot.y * h;

        switch (type)
        {
            case 1://上对齐
                for (int i = 1; i < rects.Count; i++)
                {
                    RectTransform trans = rects[i];
                    float th = trans.sizeDelta.y * trans.localScale.y;
                    Vector3 pos = trans.position;
                    pos.y = y + h - th + trans.pivot.y * th;
                    trans.position = pos;
                }


                break;
            case 2://左对齐
                for (int i = 1; i < rects.Count; i++)
                {
                    RectTransform trans = rects[i];
                    float tw = trans.sizeDelta.x * trans.lossyScale.x;
                    Vector3 pos = trans.position;
                    pos.x = x + tw*trans.pivot.x;
                    trans.position = pos;
                }
                break;
            case 3://右对齐
                for (int i = 1; i < rects.Count; i++)
                {
                    RectTransform trans = rects[i];
                    float tw = trans.sizeDelta.x * trans.lossyScale.x;
                    Vector3 pos = trans.position;
                    pos.x = x+ w - tw + tw * trans.pivot.x;
                    trans.position = pos;
                }
                break;
            case 4://下对齐
                for (int i = 1; i < rects.Count; i++)
                {
                    RectTransform trans = rects[i];
                    float th = trans.sizeDelta.y * trans.localScale.y;
                    Vector3 pos = trans.position;
                    pos.y = y + th*trans.pivot.y;
                    trans.position = pos;
                }
                break;
            case 5://水平对齐
                for (int i = 1; i < rects.Count; i++)
                {
                    RectTransform trans = rects[i];
                    float th = trans.sizeDelta.y * trans.localScale.y;
                    Vector3 pos = trans.position;
                    pos.y = y + 0.5f * h - 0.5f*th + th * trans.pivot.y;
                    trans.position = pos;
                }
                break;
            case 6://垂直对齐
                for (int i = 1; i < rects.Count; i++)
                {
                    RectTransform trans = rects[i];
                    float tw = trans.sizeDelta.x * trans.lossyScale.x;
                    Vector3 pos = trans.position;
                    pos.x = x + 0.5f * w - 0.5f * tw + tw * trans.pivot.x;
                    trans.position = pos;
                }
                break;
        }
    }

}