1:NSURL初始化方法:

NSURL *url=[NSURL URLWithString:@"http://www.baidu.com?id=1"];

2:解决NSURL初始化失败的相关解决方案.

将传进来的NSString 进行 UTF8 转码即可.

1:针对 URLWithString 初始化失败的解决方案

NSString *strLocalHtml = @"file:///Users/amarishuyi/Desktop/My IPhone Life/WebDeveloper/WebPlug-in/ExtEditor/DataPage/KMQT/Ext-HTMLEditor.html";
strLocalHtml = [NSString stringWithFormat:@"%@?Value=%@",strLocalHtml,self.txtUrl.text];
strLocalHtml= [strLocalHtml stringByAddingPercentEscapesUsingEncoding:NSUTF8StringEncoding];
NSURL * url=[NSURL URLWithString:strLocalHtml];

2:针对 fileURLWithPath 初始化失败的解决方案

self.filePathString = [self.filePathString stringByReplacingPercentEscapesUsingEncoding:NSUTF8StringEncoding];
NSURL *url = [NSURL fileURLWithPath:self.filePathString];

转码成功后 会自动 在字符串左侧添加 "file:///"

3:NSURL 成功初始化后可以获取的参数 (摘自:NSURL 学习 )

NSURL *url = [NSURL URLWithString:  @"http://www.baidu.com/s?tn=baiduhome_pg&bs=NSRUL&f=8&rsv_bp=1&rsv_spt=1&wd=NSurl&inputT=2709"];   
NSLog(@"Scheme: %@", [url scheme]);  
NSLog(@"Host: %@", [url host]);  
NSLog(@"Port: %@", [url port]);      
NSLog(@"Path: %@", [url path]);      
NSLog(@"Relative path: %@", [url relativePath]); 
NSLog(@"Path components as array: %@", [url pathComponents]);         
NSLog(@"Parameter string: %@", [url parameterString]);    
NSLog(@"Query: %@", [url query]);        
NSLog(@"Fragment: %@", [url fragment]);
NSLog(@"User: %@", [url user]);
NSLog(@"Password: %@", [url password]);

结果如下:

2012-03-31 18:22:20.904 SmallDemoList[5473:11603] 12131232
2012-03-31 18:22:20.907 SmallDemoList[5473:11603] Scheme: http
2012-03-31 18:22:20.907 SmallDemoList[5473:11603] Host: www.baidu.com
2012-03-31 18:22:20.907 SmallDemoList[5473:11603] Port: (null)
2012-03-31 18:22:20.907 SmallDemoList[5473:11603] Path: /s
2012-03-31 18:22:20.907 SmallDemoList[5473:11603] Relative path: /s
2012-03-31 18:22:20.907 SmallDemoList[5473:11603] Path components as array: (
    "/",
    s
)
2012-03-31 18:22:20.916 SmallDemoList[5473:11603] Parameter string: (null)
2012-03-31 18:22:20.917 SmallDemoList[5473:11603] Query: tn=baiduhome_pg&bs=NSRUL&f=8&rsv_bp=1&rsv_spt=1&wd=NSurl&inputT=2709
2012-03-31 18:22:20.917 SmallDemoList[5473:11603] Fragment: (null)
2012-03-31 18:22:20.917 SmallDemoList[5473:11603] User: (null)
2012-03-31 18:22:20.917 SmallDemoList[5473:11603] Password: (null)

4:根据文件名称和文件后缀获取程序包内容文件的路径

NSURL *urlKindEditor = [[NSBundlemainBundle]URLForResource:@"simple"withExtension:@"html"subdirectory:@"KindEditor/examples"]; 

URLForResource:文件名称

withExtension:文件后缀

subdirectory:在程序包中的哪个子目录中寻找. 

如果没有找到将会返回nil

找到后返回如下路径: file://localhost/Users/amarishuyi/Library/Application%20Support/iPhone%20Simulator/5.1/Applications/FB0CDABC-D0E2-45FF-AA2C-959E8A65ADB4/SmallDemoList.app/KindEditor/examples/simple.html

5:对比两个URL 是否相等

[url isEqual:[_audioPlayer url]]