Question

如何从txt文件中删除密钥和密钥值？例如，如果用户想要从此文件中删除名为Sarah的人：

    function addpoint(map,x,y,msg,type)
    {
    var LatLng = new google.maps.LatLng(x,y);
    var mi= getMarkerImage(type);
    var marker = new google.maps.Marker({position:LatLng,icon:mi,map: map, title: type});
var infowindow = new google.maps.InfoWindow({ content: '' });
if(msg!="")
{
google.maps.event.addListener(marker, 'click', function() {
if(last_infowindow){
    last_infowindow.close();
}
infowindow.content = msg;
infowindow.open(map,marker);
last_infowindow = infowindow;
});
}
return LatLng;
}

目前我有以下内容：

Joe,Bloggs,J.bloggs@example.com,01269 512355, 1, 0, 0, 0,
Sarah,Brown,S.brown@example.com,01866 522555, 1, 0,  0, 0,
…

代码已被接受，但它不会更改txt文件。我觉得我必须将更新后的信息写回txt文件，但我不知道该怎么做。

L = open("players.txt","r+")

delete_name1 = raw_input ("Enter the first name of the person you wish to delete: ")
for line in L:
    s = line.strip()
    string = s.split(",")
    if delete_name1 == string[0]:
        del string[:8] # Doesn't work
        print delete_name1 + " has been deleted."
L.close() # Closes the file to free us usage space.

Answer 1

如果文件很小，只需重写整个文件即可。对于文本文件和内置函数，这是一种简单的方法：

with open(filename) as input_file:
    data = []
    for line in input_file:
        if not line.startswith("Sarah,Brown"):
            data.append(line)

with open(filename, 'w') as output_file:
    for d in data:
        output_file.write(d + '\n')

Answer 2

要修改文件，您必须完全覆盖该文件。这是一个简短的例子：

1,Trevor,H
2,Matt,D

使用输入文件运行：

Trevor,H
Matt,D

输出结果为：

required

从CSV中删除输入与列匹配的行

2 个答案: