IOS --- Summary of common methods

IOS --- Summary of common methods

In the last two months, I have encountered some amazing problems in developing a static library of my own company, but I have finally solved them. I would like to share with you my solutions.

1. sha1 encryption:

 

+ (NSString *) sha1 :( NSString *) input {

If (! Input | [inputisEqualToString: @]) {

Return @;

}

 

// Const char * cstr = [input cStringUsingEncoding: NSUTF8StringEncoding];

// NSData * data = [NSData dataWithBytes: cstr length: input. length];

// Replace the above two lines of code with the following line of code because the above lines will lose data when encrypting Chinese characters.

NSData * data = [inputdataUsingEncoding: NSUTF8StringEncoding];

 

Uint8_t digest [CC_SHA1_DIGEST_LENGTH];

CC_SHA1 (data. bytes, (unsignedint) data. length, digest );

NSMutableString * output = [NSMutableStringstringWithCapacity: CC_SHA1_DIGEST_LENGTH * 2];

For (int I = 0; I

[Output appendFormat: @ % 02x, digest [I];

}

Return output;

}

2. parse json strings

 

+ (Id) getJsonObjectWithJsonStr :( NSString *) jsonStr {

If (jsonStr = nil ){

Returnnil;

}

 

// The following two lines of code are used to prevent the json string from containing special characters of url encode.

JsonStr = [(NSString *) jsonStrstringByReplacingOccurrencesOfString: @ + withString: @];

 

JsonStr = [jsonStr stringByReplacingPercentEscapesUsingEncoding: NSUTF8StringEncoding];

NSData * jsonData = [jsonStrdataUsingEncoding: NSUTF8StringEncoding];

NSError * error;

Id object = [NSJSONSerializationJSONObjectWithData: jsonData options: NSJSONReadingMutableContainerserror: & error];

If (error ){

LGLog (@ json parsing failed: % @, error );

Returnnil;

}

Return object;

}

3. Determine whether the string contains Chinese Characters

 

+ (BOOL) IsChinese :( NSString *) str {

For (int I = 0; I <[strlength]; I ++ ){

Int a = [strcharacterAtIndex: I];

If (a> 0x4e00 & a <0x9fff ){

ReturnYES;

}

} ReturnNO;

}

4. Identify the jailbreaking machine because cydia is installed on all jailbreaking devices.

 

+ (BOOL) isJailBreak

{

If ([[UIApplicationsharedApplication] canOpenURL: [NSURLURLWithString: @ cydia: //]) {

NSLog (@ The device is jail broken !);

ReturnYES;

}

NSLog (@ The device is NOT jail broken !);

ReturnNO;

}

5. dynamically calculate the label height based on the text content

After specifying the width of the label, call the [label sizeToFit] method. There are no problems in iPhone 5S, iPhone 6, and iPhone 6 Plus, and there are no other devices available for testing!