如何处理plist中的浮点值

时间:2010-04-14 01:58:53

标签: iphone objective-c plist

我正在使用某些php生成的Web服务器读取plist。当我在我的iphone应用程序中将其读入NSArray,然后使用NSLog将NSArray吐出来检查它时,我看到浮点值被视为字符串。我希望将“距离”值视为数字而不是字符串。这个plist显示在一个表视图中,它可以按距离排序,但问题是距离被排序为一个字符串,所以我得到了一些有趣的排序结果。

我可以将距离值从NSArray中的字符串转换为float吗?或者也许是一个更简单的解决方案,比如调整plist定义,或者NSMutableURLRequest代码中的某些东西?

我的plist看起来像这样:

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE plist PUBLIC "-//Apple//DTD PLIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.0.dtd">
<plist version="1.0">
<array>
  <dict>
    <key>name</key>
    <string>Pizza Joint</string>
    <key>distance</key>
    <string>2.1</string>
  </dict>
  <dict>
    <key>name</key>
    <string>Burger Kang</string>
    <key>distance</key>
    <string>5</string>
  </dict>
</array>
</plist>

将其读入NSArray后,每个NSLog看起来像这样:

    result: (
      {
        distance = "2.1";
        name = "Pizza Joint";
      },
        {
        distance = 5;
        name = "Burger Kang";
      }
    )

以下是检索plist的Objective-C代码:

// Set up url request
// postData and postLength are left out, but I can post in this question if needed.
NSMutableURLRequest *request = [[[NSMutableURLRequest alloc] init] autorelease];
[request setURL:[NSURL URLWithString:@"http://mysite.com/get_plist.php"]];  
[request setHTTPMethod:@"POST"];
[request setValue:postLength forHTTPHeaderField:@"Content-Length"];
[request setValue:@"application/x-www-form-urlencoded charset=utf-8" forHTTPHeaderField:@"Content-Type"];
[request setHTTPBody:postData];     


NSError *error;
NSURLResponse *response;
NSData *result = [NSURLConnection sendSynchronousRequest:request returningResponse:&response error:&error];
NSString *string = [[NSString alloc] initWithData:result encoding:NSUTF8StringEncoding];
// libraryContent is an NSArray
self.libraryContent = [string propertyList];
NSLog(@"result: %@", self.libraryContent);

3 个答案:

答案 0 :(得分:10)

您可以在plist文件中使用real键类型,例如:

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE plist PUBLIC "-//Apple//DTD PLIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.0.dtd">
<plist version="1.0">
<dict>
        <key>value</key>
        <real>1</real>
</dict>
</plist>

答案 1 :(得分:3)

此表列出了您可以在plist中使用的可能类型:

Table 2-1: Property list types and their various representations

答案 2 :(得分:1)

使用<real>元素,而不是<string>