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A utility box for NSStrings. Converts to: SHA1, NSNumber. Test for being empty. Contains substrings and replace substrings from NSDictionary.
#import <Foundation/Foundation.h>
@interface NSString (Extensions)
+ (NSString *)stringToSha1:(NSString *)str;
- (NSNumber*)stringToNSNumber;
- (BOOL)isEmpty;
- (BOOL)stringContainsSubString:(NSString *)subString;
- (NSString *)stringByReplacingStringsFromDictionary:(NSDictionary *)dict;
#import "NSString+Extensions.h"
#import <CommonCrypto/CommonDigest.h>
@implementation NSString (Extensions)
+ (NSString*)stringToSha1:(NSString*)str {
const char *s = [str cStringUsingEncoding:NSUTF8StringEncoding];
NSData *keyData = [NSData dataWithBytes:s length:strlen(s)];
// This is the destination
uint8_t digest[CC_SHA1_DIGEST_LENGTH] = {0};
// This one function does an unkeyed SHA1 hash of your hash data
CC_SHA1(keyData.bytes, keyData.length, digest);
// Now convert to NSData structure to make it usable again
NSData *out = [NSData dataWithBytes:digest length:CC_SHA1_DIGEST_LENGTH];
NSString *hash = [out description];
NSCharacterSet *doNotWants = [NSCharacterSet characterSetWithCharactersInString:@"<> "];
hash = [[hash componentsSeparatedByCharactersInSet:doNotWants] componentsJoinedByString:@""];
return hash;
- (NSNumber*)stringToNSNumber {
NSNumberFormatter* tmpFormatter = [[NSNumberFormatter alloc] init];
[tmpFormatter setNumberStyle:NSNumberFormatterDecimalStyle];
NSNumber* theNumber = [tmpFormatter numberFromString:self];
return theNumber;
- (BOOL)isEmpty {
if ([self length] <= 0 || self == (id)[NSNull null] || self == nil) {
return YES;
return NO;
- (BOOL)stringContainsSubString:(NSString *)subString {
NSRange aRange = [self rangeOfString:subString];
if (aRange.location == NSNotFound) {
return NO;
return YES;
- (NSString*)stringByReplacingStringsFromDictionary:(NSDictionary*)dict {
NSMutableString* string = [self mutableCopy];
for (NSString* target in dict) {
[string replaceOccurrencesOfString:target withString:[dict objectForKey:target] options:0 range:NSMakeRange(0, [string length])];
return string;
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