substringFromIndex 和 substringToIndex用法，

substringFromIndex 和 substringToIndex用法，

NSString *testsubstringToorFromIndex = @"test1234";
    NSString *fromIndexstring = [testsubstringToorFromIndex substringFromIndex:2];
    
    NSString *toIndexstring = [testsubstringToorFromIndex substringToIndex:2];
    NSLog(@"subtringfromindex is %@",fromIndexstring);
    NSLog(@"subtringToindex is %@",toIndexstring);

输出结果

2014-11-29 06:23:59.634 sdktest[587:11024] subtringfromindex is st1234

2014-11-29 06:23:59.634 sdktest[587:11024] subtringToindex is te

- (NSString *)substringFromIndex:(NSUInteger)anIndex
Description
Returns a new string containing the characters of the receiver from the one at a given index to the end.

返回一个字符串，这个字符串截取接受对象字符串范围是给定索引index到这个字符串的结尾

- (NSString *)substringToIndex:(NSUInteger)anIndex
Description
Returns a new string containing the characters of the receiver up to, but not including, the one at a given index.

返回一个字符串，这个字符串截取接受对象字符穿范围是从索引0到给定的索引index