Common methods of NSString in Foundation

1. Case operation

 //  all uppercase    result ABC  [@ " ABC    uppercasestring]  //  all lowercase  //  result BCD  [@ " bcd   "  lowercasestring]  //  first uppercase  //  result ACB  [@ " ACB  "  Capitalizedstring] 

2. String comparisons

//Compare two strings for the same contentbool b =[str isequaltostring:str2];  
// Two string content comparison //< Span style= "color: #008000;" > Nscomparisonresult result = {nsorderedascending, nsorderedsame,nsordereddescending } // nsorderedascending right > left // Nsorderedsame content same //  nsordereddescending left > right  Nscomparisonresult Result = [str compare:str2]; ignore case to compare 
 nscomparisonresult result = [str CASEINSENSITIVECOMPARE:STR2];  
           

3. String Search

//determines whether a string starts with ABC[@ "ABCDFA"Hasprefix:@ "ABC"]; //determines whether a string is a BCD end[@ "ADBCD"Hassuffix:@ "BCD"]; //determines whether the string contains the specified string, returns the position and lengthNsrange range = [@ "123456"Rangeofstring:@ "456"]; //Reverse SearchNsrange range = [@"123456456qweasasd456"Rangeofstring:@"456"Options:nsbackwardssearch]; //Search by specified rangeNsrange range = Nsmakerange (0,9); Range= [@"123456456qweasasd456"Rangeofstring:@"456"Options:nsbackwardssearch Range:range];

Common methods of NSString in Foundation