手机内存文件存储练习

Posted 2020-07-13 安然罒

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把用户的注册信息存储到文件里，登录成功后读出并显示出来，把代码发到博客上。

 1 <?xml version="1.0" encoding="utf-8"?>
 2 <RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
 3     xmlns:tools="http://schemas.android.com/tools"
 4     android:layout_width="match_parent"
 5     android:layout_height="match_parent"
 6     android:paddingBottom="@dimen/activity_vertical_margin"
 7     android:paddingLeft="@dimen/activity_horizontal_margin"
 8     android:paddingRight="@dimen/activity_horizontal_margin"
 9     android:paddingTop="@dimen/activity_vertical_margin"
10     tools:context="com.example.wang.xuexi.NCMActivity">
11 
12     <EditText
13         android:layout_width="match_parent"
14         android:layout_height="wrap_content"
15         android:hint="用户名称"
16         android:id="@+id/et_2"/>
17     <EditText
18         android:layout_width="match_parent"
19         android:layout_height="wrap_content"
20         android:hint="密码"
21         android:inputType="numberPassword"
22         android:layout_below="@id/et_2"
23         android:id="@+id/et_3"/>
24     <LinearLayout
25         android:layout_width="match_parent"
26         android:layout_height="wrap_content"
27         android:layout_below="@id/et_3">
28         <Button
29             android:layout_width="0dp"
30             android:layout_height="wrap_content"
31             android:text="登陆"
32             android:id="@+id/bt_1"
33             android:onClick="bt1_OnClick"
34             android:layout_weight="1"/>
35         <Button
36             android:layout_width="0dp"
37             android:layout_height="wrap_content"
38             android:text="注册"
39             android:id="@+id/bt_2"
40             android:onClick="bt2_OnClick"
41             android:layout_weight="1"/>
42     </LinearLayout>
43 </RelativeLayout>

登录界面.xml

 1 <?xml version="1.0" encoding="utf-8"?>
 2 <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
 3     xmlns:tools="http://schemas.android.com/tools"
 4     android:layout_width="match_parent"
 5     android:layout_height="match_parent"
 6     android:paddingBottom="@dimen/activity_vertical_margin"
 7     android:paddingLeft="@dimen/activity_horizontal_margin"
 8     android:paddingRight="@dimen/activity_horizontal_margin"
 9     android:paddingTop="@dimen/activity_vertical_margin"
10     tools:context="com.example.wang.xuexi.NCZActivity"
11     android:orientation="vertical">
12 
13     <EditText
14         android:layout_width="match_parent"
15         android:layout_height="wrap_content"
16         android:hint="用户名称"
17         android:id="@+id/et_1"/>
18     <EditText
19         android:layout_width="match_parent"
20         android:layout_height="wrap_content"
21         android:hint="用户代码"
22         android:id="@+id/et_2"/>
23     <EditText
24         android:layout_width="match_parent"
25         android:layout_height="wrap_content"
26         android:hint="密码"
27         android:id="@+id/et_3"/>
28     <LinearLayout
29         android:layout_width="match_parent"
30         android:layout_height="wrap_content"
31         >
32         <Button
33             android:layout_width="0dp"
34             android:layout_height="wrap_content"
35             android:text="取消"
36             android:id="@+id/bt_1"
37             android:layout_weight="1"/>
38         <Button
39             android:layout_width="0dp"
40             android:layout_height="wrap_content"
41             android:text="确定"
42             android:id="@+id/bt_2"
43             android:layout_weight="1"
44             android:onClick="bt1_OnClick"/>
45     </LinearLayout>
46 
47 </LinearLayout>

 1 <?xml version="1.0" encoding="utf-8"?>
 2 <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
 3     xmlns:tools="http://schemas.android.com/tools"
 4     android:layout_width="match_parent"
 5     android:layout_height="match_parent"
 6     android:paddingBottom="@dimen/activity_vertical_margin"
 7     android:paddingLeft="@dimen/activity_horizontal_margin"
 8     android:paddingRight="@dimen/activity_horizontal_margin"
 9     android:paddingTop="@dimen/activity_vertical_margin"
10     tools:context="com.example.wang.xuexi.NCTActivity"
11     android:orientation="vertical">
12 
13 
14     <TextView
15         android:layout_width="match_parent"
16         android:layout_height="60dp"
17         android:id="@+id/tv_1"/>
18 
19     <TextView
20         android:layout_width="match_parent"
21         android:layout_height="60dp"
22         android:id="@+id/tv_2"/>
23 
24     <TextView
25         android:layout_width="match_parent"
26         android:layout_height="60dp"
27         android:id="@+id/tv_3"/>
28 
29 </LinearLayout>

显示界面.xml

  1 package com.example.wang.xuexi;
  2 
  3 import android.content.Intent;
  4 import android.support.v7.app.AppCompatActivity;
  5 import android.os.Bundle;
  6 import android.view.View;
  7 import android.widget.EditText;
  8 import android.widget.Toast;
  9 
 10 import java.io.FileInputStream;
 11 
 12 public class NCMActivity extends AppCompatActivity {
 13 
 14     EditText et_2;
 15 
 16     EditText et_3;
 17 
 18 
 19     @Override
 20     protected void onCreate(Bundle savedInstanceState) {
 21         super.onCreate(savedInstanceState);
 22         setContentView(R.layout.activity_ncm);
 23 
 24         et_2=(EditText)findViewById(R.id.et_2);
 25         et_3=(EditText)findViewById(R.id.et_3);
 26     }
 27 
 28     public void bt2_OnClick(View v)
 29     {
 30         Intent intent=new Intent(this,NCZActivity.class);
 31 
 32         startActivity(intent);
 33     }
 34 
 35 
 36 
 37     public void bt1_OnClick(View v)
 38     {
 39         String name="";
 40         String code="";
 41         String pword="";
 42 
 43         try {
 44 
 45             FileInputStream fis1=openFileInput("name.txt");
 46             byte [] b1=new byte[1024];
 47             int i1=0;
 48             while ((i1=fis1.read(b1))>0)
 49             {
 50                 String name1=new String(b1,0,i1);
 51 
 52                 name+=name1;
 53             }
 54             fis1.close();
 55 
 56             FileInputStream fis2=openFileInput("code.txt");
 57             byte [] b2=new byte[1024];
 58             int i2=0;
 59             while ((i2=fis2.read(b2))>0)
 60             {
 61                 String code1=new String(b2,0,i2);
 62 
 63                 code+=code1;
 64             }
 65             fis2.close();
 66 
 67             FileInputStream fis3=openFileInput("password.txt");
 68             byte [] b3=new byte[1024];
 69             int i3=0;
 70             while ((i3=fis3.read(b3))>0)
 71             {
 72                 String pword1=new String(b3,0,i3);
 73 
 74                 pword+=pword1;
 75             }
 76             fis3.close();
 77 
 78         }
 79         catch (Exception e)
 80         {
 81 
 82         }
 83 
 84 
 85         String et_code=et_2.getText().toString();
 86         String et_pass=et_3.getText().toString();
 87         if (et_code.trim().length()==0||et_pass.trim().length()==0)
 88         {
 89             Toast.makeText(NCMActivity.this, "用户名或密码不能为空", Toast.LENGTH_SHORT).show();
 90             return;
 91         }
 92 
 93         if (et_code ==null ||et_code.equals(code))
 94         {
 95             Toast.makeText(NCMActivity.this, "用户未注册", Toast.LENGTH_SHORT).show();
 96             return;
 97         }
 98 
 99 
100 
101         if (et_pass==null||et_pass.equals(pword))
102         {
103             Toast.makeText(NCMActivity.this, "密码错误", Toast.LENGTH_SHORT).show();
104 
105             return;
106         }
107         else
108         {
109             Toast.makeText(NCMActivity.this,"用户登录成功",Toast.LENGTH_LONG).show();
110 
111             Intent intent=new Intent(this,NCTActivity.class);
112 
113             startActivity(intent);
114 
115             finish();
116 
117             }
118 
119 
120     }
121 }

  1 package com.example.wang.xuexi;
  2 
  3 import android.content.Intent;
  4 import android.support.v7.app.AppCompatActivity;
  5 import android.os.Bundle;
  6 import android.view.View;
  7 import android.widget.Button;
  8 import android.widget.EditText;
  9 import android.widget.Toast;
 10 
 11 import java.io.File;
 12 import java.io.FileOutputStream;
 13 import java.io.PrintStream;
 14 
 15 public class NCZActivity extends AppCompatActivity {
 16 
 17     EditText et_1;
 18 
 19     EditText et_2;
 20 
 21     EditText et_3;
 22 
 23     Button bt_1;
 24 
 25     @Override
 26     protected void onCreate(Bundle savedInstanceState) {
 27         super.onCreate(savedInstanceState);
 28         setContentView(R.layout.activity_ncz);
 29 
 30 
 31         et_1 = (EditText) findViewById(R.id.et_1);
 32         et_2 = (EditText) findViewById(R.id.et_2);
 33         et_3 = (EditText) findViewById(R.id.et_3);
 34 
 35         bt_1 = (Button) findViewById(R.id.bt_1);
 36 
 37         bt_1.setOnClickListener(new View.OnClickListener() {
 38             @Override
 39             public void onClick(View v) {
 40                 setResult(RESULT_CANCELED, null);
 41                 finish();
 42             }
 43         });
 44     }
 45 
 46 
 47     public void bt1_OnClick(View v) {
 48 
 49         String user_name = et_1.getText().toString();
 50 
 51         if (user_name == null || user_name.trim().length() == 0) {
 52             Toast.makeText(this, "请正确输入用户名", Toast.LENGTH_SHORT).show();
 53             return;
 54         }
 55 
 56         String user_code = et_2.getText().toString();
 57 
 58         if (user_code == null || user_code.trim().length() == 0) {
 59             Toast.makeText(this, "请正确输入用户代码", Toast.LENGTH_SHORT).show();
 60             return;
 61         }
 62 
 63         String pass_word = et_3.getText().toString();
 64 
 65         if (pass_word == null || pass_word.trim().length() == 0) {
 66             Toast.makeText(this, "请正确填写用户密码", Toast.LENGTH_SHORT).show();
 67             return;
 68         }
 69 
 70 
 71         try {
 72 
 73             FileOutputStream fos1 = openFileOutput("name.txt", MODE_PRIVATE);
 74             PrintStream ps1 = new PrintStream(fos1);
 75             ps1.println(user_name);
 76 
 77             FileOutputStream fos2 = openFileOutput("code.txt", MODE_PRIVATE);
 78             PrintStream ps2 = new PrintStream(fos2);
 79             ps2.println(user_code);
 80 
 81             FileOutputStream fos3 = openFileOutput("password.txt", MODE_PRIVATE);
 82             PrintStream ps3 = new PrintStream(fos1);
 83             ps3.println(pass_word);
 84 
 85             ps1.close();
 86             ps2.close();
 87             ps3.close();
 88 
 89             fos3.close();
 90 
 91             Toast.makeText(NCZActivity.this, "注册并保存成功", Toast.LENGTH_SHORT).show();
 92 
 93         } catch (Exception e) {
 94 
 95             Toast.makeText(NCZActivity.this, "注册并保存失败", Toast.LENGTH_SHORT).show();
 96         }
 97 
 98         Intent intent = new Intent(this,NCMActivity.class);
 99 
100         startActivity(intent);
101 
102         finish();
103 
104     }
105 
106 
107     }

 1 package com.example.wang.xuexi;
 2 
 3 import android.support.v7.app.AppCompatActivity;
 4 import android.os.Bundle;
 5 import android.widget.TextView;
 6 
 7 import java.io.FileInputStream;
 8 
 9 public class NCTActivity extends AppCompatActivity {
10 
11     TextView tv_1;
12     TextView tv_2;
13     TextView tv_3;
14     String name="";
15     String code="";
16     String pword="";
17 
18     @Override
19     protected void onCreate(Bundle savedInstanceState) {
20         super.onCreate(savedInstanceState);
21         setContentView(R.layout.activity_nct);
22 
23         tv_1=(TextView)findViewById(R.id.tv_1);
24         tv_2=(TextView)findViewById(R.id.tv_2);
25         tv_3=(TextView)findViewById(R.id.tv_3);
26 
27         try {
28 
29             FileInputStream fis1=openFileInput("name.txt");
30             byte [] b1=new byte[1024];
31             int i1=0;
32             while ((i1=fis1.read(b1))>0)
33             {
34                 String name1=new String(b1,0,i1);
35 
36                 name+=name1;
37             }
38             tv_1.setText("用户名称："+name);
39             fis1.close();
40 
41             FileInputStream fis2=openFileInput("code.txt");
42             byte [] b2=new byte[1024];
43             int i2=0;
44             while ((i2=fis2.read(b2))>0)
45             {
46                 String code1=new String(b2,0,i2);
47 
48                 code+=code1;
49             }
50             tv_2.setText("用户代码："+code);
51             fis2.close();
52 
53             FileInputStream fis3=openFileInput("password.txt");
54             byte [] b3=new byte[1024];
55             int i3=0;
56             while ((i3=fis3.read(b3))>0)
57             {
58                 String pword1=new String(b3,0,i3);
59 
60                 pword+=pword1;
61             }
62             tv_3.setText("用户密码："+pword);
63             fis3.close();
64 
65         }
66         catch (Exception e)
67         {
68 
69 
70         }
71 }}

显示.java

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