1首先要遍历所有的资源

过滤出.mat的资源，也就是Material,然后通过Shader名来查找对应的引用的材质，然后可以将这些路径名打出来。

改进

打印出所有的路径名还要自己去找不是很方便，后面将它输出到面板上，并且可以快速定位，用到了编辑器开发，editorlayout,

ObjectField

核心逻辑
EditorGUILayout.ObjectField("", go, typeof(Material), false);                    

最后因为路径太长需要修改左侧的长度，后面引入了GUIContent作为第一个参数，然后以为需要长度长一点，
引入逻辑EditorGUIUtility.labelWidth = 400，设置他的长度。

最后上代码

using System.Collections;
using System.Collections.Generic;
using System.IO;
using System.Text;
using UnityEditor;
using UnityEngine;
using System.Threading;
 
public class SearchShader :EditorWindow
{
 
    // public static string FilePath = "Assets/Materials";
    public static string FilePath = "Assets";
    //搜索固定文件夹中的所有Material的路径
    public static List<string> listMatrials;
    public static List<string> listTargetMaterial;
 
    public static string selectedShaderName;
 
    public static StringBuilder sb;
    static public SearchShader instance;
    public Dictionary<string, BetterList<string>> dict;
    public BetterList<string> allPath;
    Vector2 mScroll = Vector2.zero;
    
    void OnEnable()
    {
        // instance = this;
    }

    void OnDisable()
    {
        // instance = null;
    }

    void OnGUI()
    {
        if (listTargetMaterial == null)
        {
            return;
        }

        mScroll = GUILayout.BeginScrollView(mScroll);

        List<string> list = listTargetMaterial;
        if (list != null && list.Count > 0)
        {
            if (NGUIEditorTools.DrawHeader("Mat"))
            {
                int count = 0;
                foreach (string item in list)
                {
                    // Debug.Log("item ----------------"+item);                    
                    count += 1;
                    Material go = AssetDatabase.LoadAssetAtPath(item, typeof(Material)) as Material;                    
                    GUIContent label1 = new GUIContent(count+"---"+item,item);                                                    
                    EditorGUIUtility.labelWidth = EditorGUIUtility.currentViewWidth * 0.6f;                                               
                    EditorGUILayout.ObjectField(label1, go, typeof(Material), false);                    
                }
            }
            // Debug.Log("当前的窗体的的宽度是----------------------------------"+EditorGUIUtility.currentViewWidth);

            list = null;
        }        

        GUILayout.EndScrollView();
    }

    [MenuItem("Assets/SearchShader", true)]
    private static bool OptionSelectAvailable()
    {
        if(Selection.activeObject == null)
        {
            return false;
        }
        return Selection.activeObject.GetType() == typeof(Shader);
    }
 
    [MenuItem("Assets/SearchShader")]
    private static void SearchConstantShader()
    {
        Debug.Log("当前选中的Shader名字：" + Selection.activeObject.name);
        sb = new StringBuilder();
 
        selectedShaderName = Selection.activeObject.name;
 
        listMatrials = new List<string>();
        listMatrials.Clear();
        listTargetMaterial = new List<string>();
        listTargetMaterial.Clear();
 
        //项目路径 eg:projectPath = D:Project/Test/Assets
        string projectPath = Application.dataPath;
 
        //eg:projectPath = D:Project/Test
        projectPath = projectPath.Substring(0, projectPath.IndexOf("Assets"));
 
        try
        {
            //获取某一文件夹中的所有Matrial的Path信息
            GetMaterialsPath(projectPath, FilePath, "Material",ref listMatrials);
        }
        catch(System.Exception e)
        {
            Debug.LogError(e);
        }
 
        for (int i = 0; i < listMatrials.Count; i++)
        {
            EditorUtility.DisplayProgressBar("Check Materials", "Current Material :" 
                + i + "/" + listMatrials.Count,(float)i/ listMatrials.Count);
 
            try
            {
                //开始Check
                BegainCheckMaterials(listMatrials[i]);
            }
            catch (System.Exception e)
            {
                EditorUtility.ClearProgressBar();
                Debug.LogError(e);
            }
        }
 
        // PrintToTxt();
        //生成界面
        EditorUtility.ClearProgressBar();
        EditorWindow.GetWindow<SearchShader>(false, "SearchShader", true).Show();
        Debug.Log("Check Success");
    }
 
    //获取某一文件夹中的所有Matrial的Path信息
    public static void GetMaterialsPath(string projectPath,string targetFilePath,string searchType,ref List<string> array)
    {
        if (Directory.Exists(targetFilePath))
        {
            string[] guids;
            //搜索
            guids = AssetDatabase.FindAssets("t:" + searchType, new[] { targetFilePath });            
            foreach (string guid in guids)
            {
                string source = AssetDatabase.GUIDToAssetPath(guid);
                string[] allStr = source.Split('.');
                // if(allStr[allStr.Length-1] == "mat")
                if(source.EndsWith(".mat"))
                {
                    listMatrials.Add(source);
                    // Debug.Log("当前的material------------"+source);
                }                                
            }
            // Debug.Log("当前material的总数是---------------"+listMatrials.Count);
        }
    }
 
    //开始检查Material
    public static void BegainCheckMaterials(string materialPath)
    {
        Material mat = AssetDatabase.LoadAssetAtPath<Material>(materialPath);
        if (mat.shader.name == selectedShaderName)
        {
            listTargetMaterial.Add(materialPath);
        }
    }
 
    public static void PrintToTxt()
    {
        //加入shader的名字
        listTargetMaterial.Add(selectedShaderName);
 
        FileInfo fi = new FileInfo(Application.dataPath + "/Materials.txt");
        if (!fi.Exists)
        {
            // fi.CreateText();   
            // fi.OpenWrite();  
            // Thread.Sleep(1000);              
            var stream =  fi.Create();
            stream.Dispose();  
        }
        // else
        {
            StreamWriter sw = new StreamWriter(Application.dataPath + "/Materials.txt");
            for (int i = 0; i < listTargetMaterial.Count - 1; i++)
            {
                sb.Append(listTargetMaterial[i] + "\n");
            }
            string useNum = string.Format("共有 {0} 个Material用到：{1}", listTargetMaterial.Count - 1, selectedShaderName);
            sb.Append(useNum + "\n");
            sb.Append("用到的shader名字为：" + selectedShaderName);
            sw.Write(sb.ToString());
 
            sw.Flush();
            sw.Close();
            sw.Dispose();
        }
    }

}

ps:脚本放在Assets下面的Editor下面，没有就创建一个