做验证码用到的,然后就把这个函数封装起来,使用时候要设置2个参数: $str设置里要被采集的字符串,比如: $str='efasfgzsrhftjxjxjhsrth'; 则在函数里面生成的字符串就回从efasfgzsrhftjxjxjhsrth里面随机抓取: $codeLen设置要生成的随机字符串,设置5,则生成5个随机字符串. 原理:随机抓取字符串,对字符串进行拼接 效果: 代码: <?php //mt_rand 获取随机数 mt_rand(min, max); $str="abcdef…

随机字符串 - 生成指定长度的字符串 -(NSString *)randomStringWithLength:(NSInteger)len { NSString *letters = @"abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789"; NSMutableString *randomString = [NSMutableString stringWithCapacity: len]; for (NSInte…

一,代码. - (void)viewDidLoad { [super viewDidLoad]; // Do any additional setup after loading the view, typically from a nib. //获取字符串的宽度 NSLog(@"获得字符串的宽度:%f",[self widthForString:@"我爱你!我爱你!我爱你!我爱你!我爱你!我爱你!我爱你!我爱你!" fontSize:10.0 andHeight:…

一,代码. - (void)viewDidLoad { [super viewDidLoad]; // Do any additional setup after loading the view. self.title=@"判断字符串是否为空"; NSLog(@"-isEmpty--%i--",[self isEmpty:@"123"]); } //判断字符串是否为空 -(BOOL)isEmpty:(NSString *)str { if(!s…

说明:生成随机字符串用到的方法有 mt_rand() 生成唯一字符串用到的方法有 md5(),uniqid(),microtime() 代码: <?php /* * 生成随机字符串 * @param int $length 生成随机字符串的长度 * @param string $char 组成随机字符串的字符串 * @return string $string 生成的随机字符串 */ function str_rand($length = 32, $char = '0123456789abcde…

代码如下: <?php /* * 生成随机字符串 * @param int $length 生成随机字符串的长度 * @param string $char 组成随机字符串的字符串 * @return string $string 生成的随机字符串 */ function str_rand($length = , $char = '0123456789abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ') { ) { return false…

一,代码: - (void)viewDidLoad { [super viewDidLoad]; // Do any additional setup after loading the view, typically from a nib. NSLog(@"---产生随机字符串---%@",[self generateTradeNO]); } //产生随机字符串 - (NSString *)generateTradeNO { static int kNumber = 15; NSSt…

原文连接 Objective-C版 // 随机生成字符串(由大小写字母.数字组成) + (NSString *)random: (int)len { char ch[len]; for (int index=0; index<len; index++) { int num = arc4random_uniform(75)+48; if (num>57 && num<65) { num = num%57+48; } else if (num>90 &&…

转换代码,崩溃日志有些是十六进制 NSString *dictString = [dict JSONFragment];//组合成的 dictString==={"content":"Sadgfdfg","phoneno":"","email":"1049055935@qq.com"}=== // 十六进制转换为普通字符串的. + (NSString *)stringFromHexStr…

using System; using System.Collections.Generic; using System.Web; using System.IO; using System.Security.Cryptography; using System.Runtime.Serialization.Json; using System.Runtime.Serialization; using System.Net; using System.Runtime.Serialization.F…