diff --git a/dsRag/static/tree.html b/dsRag/static/tree.html
index a2336f46..6465ee2e 100644
--- a/dsRag/static/tree.html
+++ b/dsRag/static/tree.html
@@ -121,18 +121,10 @@
     }
 
     // 初始化数据
-    $.ajax({
-        url: "/api/tree-data",
-        type: "GET",
-        success: function (res) {
-            if (res.code === 0) {
-                treeData = res.data;
-                updateTable();
-            }
-        }
-    });
-
-
+    // Move this declaration outside the AJAX call
+    var allNodes = [];
+    
+    // Add flattenTree function definition before the AJAX call
     function flattenTree(nodes) {
         var result = [];
         nodes.forEach(node => {
@@ -143,17 +135,107 @@
         });
         return result;
     }
-
+    
+    $.ajax({
+        url: "/api/tree-data",
+        type: "GET",
+        success: function(res) {
+            if (res.code === 0) {
+                treeData = res.data;
+                allNodes = flattenTree(treeData);
+                updateTable();
+            }
+        }
+    });
+    
+    // 修改prerequisiteUpdate和relatedUpdate函数
     function prerequisiteUpdate(nodeId) {
         const node = findNodeById(treeData, nodeId);
-        if (node) {
-            alert(`先修知识 Node ID: ${node.id}\nNode Title: ${node.title}`);
-        } else {
+        if (!node) {
             console.error('Node not found:', nodeId);
+            return;
         }
+        
+        // 创建模态框容器
+        const modal = document.createElement('div');
+        modal.style.position = 'fixed';
+        modal.style.top = '50%';
+        modal.style.left = '50%';
+        modal.style.transform = 'translate(-50%, -50%)';
+        modal.style.width = '500px';
+        modal.style.padding = '20px';
+        modal.style.backgroundColor = 'white';
+        modal.style.border = '1px solid #ccc';
+        modal.style.borderRadius = '5px';
+        modal.style.boxShadow = '0 0 10px rgba(0,0,0,0.2)';
+        modal.style.zIndex = '1000';
+        
+        // 创建标题和关闭按钮
+        const header = document.createElement('div');
+        header.style.display = 'flex';
+        header.style.justifyContent = 'space-between';
+        header.style.alignItems = 'center';
+        header.style.marginBottom = '15px';
+        
+        const title = document.createElement('h3');
+        title.textContent = '选择先修知识';
+        title.style.margin = '0';
+        
+        const closeBtn = document.createElement('button');
+        closeBtn.innerHTML = '×';
+        closeBtn.style.background = 'none';
+        closeBtn.style.border = 'none';
+        closeBtn.style.fontSize = '20px';
+        closeBtn.style.cursor = 'pointer';
+        closeBtn.onclick = function() {
+            document.body.removeChild(modal);
+        };
+        
+        header.appendChild(title);
+        header.appendChild(closeBtn);
+        
+        // 创建多选下拉框
+        const select = document.createElement('select');
+        select.multiple = true;
+        select.style.width = '100%';
+        select.style.height = '200px';
+        select.style.margin = '10px 0';
+        select.style.padding = '5px';
+        
+        // 添加选项
+        allNodes.forEach(n => {
+            if (n.id !== nodeId) {
+                const option = document.createElement('option');
+                option.value = n.id;
+                option.text = n.title;
+                select.appendChild(option);
+            }
+        });
+        
+        // 创建确定按钮
+        const button = document.createElement('button');
+        button.textContent = '确定';
+        button.style.padding = '8px 16px';
+        button.style.backgroundColor = '#4CAF50';
+        button.style.color = 'white';
+        button.style.border = 'none';
+        button.style.borderRadius = '4px';
+        button.style.cursor = 'pointer';
+        button.onclick = function() {
+            document.body.removeChild(modal);
+        };
+        
+        // 添加到模态框
+        modal.appendChild(header);
+        modal.appendChild(select);
+        modal.appendChild(button);
+        
+        // 添加到页面
+        document.body.appendChild(modal);
     }
 
     function relatedUpdate(nodeId) {
+        // 同样修改relatedUpdate函数
         const node = findNodeById(treeData, nodeId);
         if (node) {
             alert(`相关知识 Node ID: ${node.id}\nNode Title: ${node.title}`);