auto save

diy.py

 # 写入同学们的捐赠明细：'小兰：12本'、'小丽：11本'、'李文：9本'、'张伟：16本'
 file1=open(r"C:\Users\admin\Desktop\test.txt","w",encoding="utf-8")
-file1.write('小兰：12本,小丽：11本,李文：9本,张伟：16本')
-file1.close()
\ No newline at end of file
+file1.write('小兰：12本\n')
+file1.write('小丽：11本\n')
+file1.write('李文：9本\n')
+file1.close()
+
+with open(r"C:\Users\admin\Desktop\test.txt","a",encoding="utf-8") as file1:
+    file1.write('张伟：16本\n')
+
+with open(r"C:\Users\admin\Desktop\test.txt","r",encoding="utf-8") as file1:
+    a=file1.read()
+    print(a)
+
+with open(r"C:\Users\admin\Desktop\test.txt","r",encoding="utf-8") as file1:
+    for data in file1:
+        if "小兰：12本" in data:
+            print("数据在里面")
\ No newline at end of file