xml

java

需要权限

//向外部空间存储文件 保存到带包名的目录    public void onclick7(View view)    {        //        if (Environment.getExternalStorageState().equals(Environment.MEDIA_MOUNTED))        {            //1.获取要存储的内容            String content = et_5.getText().toString();            //2.获取外部存储带包名的目录 ——只到根目录           // String sdpath = Environment.getExternalStorageDirectory().getAbsolutePath();            //Toast.makeText(Activitydata.this, "sdpath= "+sdpath, Toast.LENGTH_LONG).show();            //参数 代表不同文件类型的子目录 如果没有就传null 获取到根目录下的带包名的目录            String sdpath = getExternalFilesDir(null).getAbsolutePath();            Toast.makeText(Activitydata.this, "sdpath= "+sdpath, Toast.LENGTH_LONG).show();            //3.构造输出流            sdpath += "/" +FILENAME;            try {                FileOutputStream fos = new FileOutputStream(sdpath,true);                //传统方式  字节数组方式                fos.write(content.getBytes("utf-8"));                fos.close();                Toast.makeText(Activitydata.this, "保存成功", Toast.LENGTH_SHORT).show();            } catch (Exception e) {                e.printStackTrace();                Toast.makeText(Activitydata.this, "保存失败", Toast.LENGTH_SHORT).show();            }        }        else        {            Toast.makeText(Activitydata.this, "sd卡没有挂载", Toast.LENGTH_SHORT).show();        }    }    //从外部存储空间中读取带包名文件    //判断是否挂载    public void onclick8(View view)    {        if (Environment.getExternalStorageState().equals(Environment.MEDIA_MOUNTED))        {            //1.获取要存储的内容            //String content = et_5.getText().toString();            //2.获取外部存储带包名的目录 ——只到根目录            // String sdpath = Environment.getExternalStorageDirectory().getAbsolutePath();            //Toast.makeText(Activitydata.this, "sdpath= "+sdpath, Toast.LENGTH_LONG).show();            //参数 代表不同文件类型的子目录 如果没有就传null 获取到根目录下的带包名的目录            String sdpath = getExternalFilesDir(null).getAbsolutePath();           // Toast.makeText(Activitydata.this, "sdpath= "+sdpath, Toast.LENGTH_LONG).show();            //3.构造输入流            sdpath += "/" +FILENAME;            try {                FileInputStream fis = new FileInputStream(sdpath);                byte[] b = new byte[1024];                int i = 0;                StringBuilder sbr = new StringBuilder();                while ((i = fis.read(b))>0)                {                    sbr.append(new String(b,0,i));                    et_6.setText(sbr);                }                fis.close();                Toast.makeText(Activitydata.this, "获取成功", Toast.LENGTH_SHORT).show();            } catch (Exception e) {                e.printStackTrace();                Toast.makeText(Activitydata.this, "获取失败", Toast.LENGTH_SHORT).show();            }        }        else        {            Toast.makeText(Activitydata.this, "sd卡没有挂载", Toast.LENGTH_SHORT).show();        }    }    //保存文件到自定义目录    public void onclick9(View view)    {        if (Environment.getExternalStorageState().equals(Environment.MEDIA_MOUNTED)) {            //1.获取要存储的内容            String content = et_5.getText().toString();            //2.获取外部存储的根目录            String sdpath = Environment.getExternalStorageDirectory().getAbsolutePath();            //在sd卡的根目录下创建子目录            sdpath += "/hanqi";            //实例化File，指向一个目录            File file = new File(sdpath);            //如果不存在创建一个            if (!file.exists()) {                //创建目录                file.mkdirs();            }                Toast.makeText(Activitydata.this, "path= " + sdpath, Toast.LENGTH_SHORT).show();                //3.创建输出流                sdpath += "/" + FILENAME;                try {                    FileOutputStream fos = new FileOutputStream(sdpath, true);                    //传统方式  字节数组方式                    fos.write(content.getBytes("utf-8"));                    fos.close();                    Toast.makeText(Activitydata.this, "保存成功", Toast.LENGTH_SHORT).show();                } catch (Exception e) {                    e.printStackTrace();                    Toast.makeText(Activitydata.this, "保存失败", Toast.LENGTH_SHORT).show();                }            }        else        {            Toast.makeText(Activitydata.this, "sd卡没有挂载", Toast.LENGTH_SHORT).show();        }    }    public void onclick10(View view){        if (Environment.getExternalStorageState().equals(Environment.MEDIA_MOUNTED))        {            //1.获取要存储的内容            //String content = et_5.getText().toString();            //2.获取外部存储带包名的目录 ——只到根目录            String sdpath = Environment.getExternalStorageDirectory().getAbsolutePath();            //Toast.makeText(Activitydata.this, "sdpath= "+sdpath, Toast.LENGTH_LONG).show();            //参数 代表不同文件类型的子目录 如果没有就传null 获取到根目录下的带包名的目录            //String sdpath = getExternalFilesDir(null).getAbsolutePath();            // Toast.makeText(Activitydata.this, "sdpath= "+sdpath, Toast.LENGTH_LONG).show();            //3.构造输入流            sdpath += "/hanqi/" +FILENAME;            Toast.makeText(Activitydata.this, ""+sdpath, Toast.LENGTH_SHORT).show();            try {                FileInputStream fis = new FileInputStream(sdpath);                byte[] b = new byte[1024];                int i = 0;                StringBuilder sbr = new StringBuilder();                while ((i = fis.read(b))>0)                {                    sbr.append(new String(b,0,i));                    et_6.setText(sbr);                }                fis.close();                Toast.makeText(Activitydata.this, "获取成功", Toast.LENGTH_SHORT).show();            } catch (Exception e) {                e.printStackTrace();                Toast.makeText(Activitydata.this, "获取失败", Toast.LENGTH_SHORT).show();            }        }        else        {            Toast.makeText(Activitydata.this, "sd卡没有挂载", Toast.LENGTH_SHORT).show();        }    }