iOS開發之一些字串常用的代碼

1、判斷字串是否相等使用isEqualToString：

   NSString *astring01 = @"This is a String!";
    NSString *astring02 = @"This is a String!";
    BOOL result = [astring01 isEqualToString:astring02];
    NSLog(@"result:%d",result);

2、判斷字元不相等：

NSString *astring01 = @"This is a String!";    
NSString *astring02 = @"This is a String!";    
if ([astring01 compare: astring02]!=NSOrderedSame ) 
{
NSLog(@"not equal");
}

3、判斷字串是否為空白。

NSString *urlString = [urlInput stringValue]; 


if (!urlString) { 


NSLog( @”NO INPUT.” ); 


} else { 

if ([urlString length] == 0 ) { 


NSLog( @”NO INPUT.” ); 


} else { 


} 


} 
}