Question

仍然是Python的新手，所以可能很容易回答。

我有一个用于for循环的列表。因此，列表中的每个项目都执行了一个操作，但我想为已发生的事情编写一个文件，如何在for循环中使用该变量为列表中的每个项目创建特定的文件名，所以在mo我有类似的东西;

mylist = ['hello', 'there', 'world']
for i in mylist:
  outputfile = open('%i.csv', 'a')
  print('hello there moon', file=outputfile)

我是否在使用%i代表列表中的各个项目的正确轨道上？

Answer 1

您可以使用format()按照以下方式执行操作：

mylist = ['hello', 'there', 'world']

for word in mylist:
    with open('{}.csv'.format(word), 'a') as f_output:
        print('hello there moon', file=f_output)

使用with之后也会自动关闭您的文件。

format()有许多可能的功能允许所有类型的字符串格式化，但简单的情况是用{}替换word，在您的情况下为module Foo def self.included(base) overrides = instance_methods.select { |method| base.instance_method(method).owner != self } raise "#{self.name} overrides #{overrides.join(', ')}" if overrides.any? end end。

Answer 2

使用以下代码。

-Wstrict-overflow=5

Answer 3

您应该使用outputfile = open('%s.csv' % i, 'a')，因为列表中的项目是字符串。

private Activity activity;
private LayoutInflater inflater;
private List<Contents> tableofcontents;
public TocAdapter(Activity activity, List<Contents> tableofcontents) {
    this.activity = activity;
    this.tableofcontents = tableofcontents;
}

@Override
public int getCount() {
    return tableofcontents == null ? 0 : tableofcontents.size();
}

@Override
public Object getItem(int location) {
    return tableofcontents.get(location);
}

@Override
public long getItemId(int position) {
    return position;
}

@Override
public View getView(int position, View convertView, ViewGroup parent) {

    if (inflater == null)
        inflater = (LayoutInflater) activity
                .getSystemService(Context.LAYOUT_INFLATER_SERVICE);
    if (convertView == null)
        convertView = inflater.inflate(R.layout.tableofcontents_view, null);
    ImageView thumbNail = (ImageView) convertView
            .findViewById(R.id.thumbnail);
    TextView name = (TextView) convertView.findViewById(R.id.name);
    Contents m = tableofcontents.get(position);
    String id = tableofcontents.get(position).getCategory_id();
    Log.d(TAG,"m Check :"+m.getCategory_id());
    Log.d(TAG,"tggCheck :"+tableofcontents.get(position).getCategory_id());
    if(tableofcontents.get(position).getCategory_id().equals(1)) {
        Glide.with(activity)
                .load(R.drawable.novels)
                .placeholder(R.mipmap.ic_launcher)
                .into(thumbNail);
    }else if(tableofcontents.get(position).getCategory_id().equals(2)){
        Glide.with(activity)
                .load(R.drawable.verses)
                .placeholder(R.mipmap.ic_launcher)
                .into(thumbNail);
    }else if(tableofcontents.get(position).getCategory_id().equals(3)) {
        Glide.with(activity)
                .load(R.drawable.songs)
                .placeholder(R.mipmap.ic_launcher)
                .into(thumbNail);
    }else if(tableofcontents.get(position).getCategory_id().equals(4)) {
        Glide.with(activity)
                .load(R.drawable.stories)
                .placeholder(R.mipmap.ic_launcher)
                .into(thumbNail);
    }else if(tableofcontents.get(position).getCategory_id().equals(5)) {
        Glide.with(activity)
                .load(R.drawable.plays)
                .placeholder(R.mipmap.ic_launcher)
                .into(thumbNail);
    }else if(tableofcontents.get(position).getCategory_id().equals(6)) {
        Glide.with(activity)
                .load(R.drawable.essay)
                .placeholder(R.mipmap.ic_launcher)
                .into(thumbNail);
    }else if(tableofcontents.get(position).getCategory_id().equals(7)) {
        Glide.with(activity)
                .load(R.drawable.others)
                .placeholder(R.mipmap.ic_launcher)
                .into(thumbNail);
    }
    name.setText(m.getName());
    return convertView;
}

Answer 4

mylist = ['hello', 'there', 'world']
for item in mylist:
   with open('%s.txt'%item,'a') as in_file:
      in_file.write('hello there moon')

Answer 5

使用f弦

这是最简单且最新的字符串格式实现。
f-Strings: A New and Improved Way to Format Strings in Python
PEP 498 - Literal String Interpolation
字符串前面带有f，并且变量位于字符串引号内，并用{}包围。
- f'{i}.csv'

mylist = ['hello', 'there', 'world']
for i in mylist:
    outputfile = open(f'{i}.csv', 'a')
    print('hello there moon', file=outputfile)

使用列表中的项目创建文件名 - for循环

5 个答案:

使用f弦