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代码片段收集

iOS

图片压缩

- (NSData *)compressImage:(UIImage *)image toByte:(NSUInteger)maxLength {    // Compress by quality    CGFloat compression = 1;    NSData *data = UIImageJPEGRepresentation(image, compression);    if (data.length < maxLength) {        return data;    }    CGFloat max = 1;    CGFloat min = 0;    for (int i = 0; i < 6; ++i) {        compression = (max + min) / 2;        data = UIImageJPEGRepresentation(image, compression);        if (data.length < maxLength * 0.9) {            min = compression;        } else if (data.length > maxLength) {            max = compression;        } else {            break;        }    }    if (data.length < maxLength) {        return data;    }    UIImage *resultImage = [UIImage imageWithData:data];    // Compress by size    NSUInteger lastDataLength = 0;    while (data.length > maxLength && data.length != lastDataLength) {        lastDataLength = data.length;        CGFloat ratio = (CGFloat)maxLength / data.length;        // Use NSUInteger to prevent white blank        CGSize size = CGSizeMake((NSUInteger)(resultImage.size.width * sqrtf(ratio)),                                 (NSUInteger)(resultImage.size.height * sqrtf(ratio)));         UIGraphicsBeginImageContext(size);        [resultImage drawInRect:CGRectMake(0, 0, size.width, size.height)];        resultImage = UIGraphicsGetImageFromCurrentImageContext();        UIGraphicsEndImageContext();        data = UIImageJPEGRepresentation(resultImage, compression);    }    return data;}

NSLog 转成 file 保存到设备沙盒文件

- (BOOL)application:(UIApplication*)application didFinishLaunchingWithOptions:(NSDictionary*)launchOptions {    [self redirectNSlogToDocumentFolder];    NSSetUncaughtExceptionHandler (&UncaughtExceptionHandler);}void UncaughtExceptionHandler(NSException *exception) {    NSArray *arr = [exception callStackSymbols];//得到当前调用栈信息    NSString *reason = [exception reason];//非常重要，就是崩溃的原因    NSString *name = [exception name];//异常类型    //打印错误信息：    NSString *errorStr = [NSString stringWithFormat:@"exception type : %@ \n crash reason : %@ \n call stack info : %@", name, reason, arr];    NSLog(@"%@",errorStr);}- (void)redirectNSlogToDocumentFolder {    NSArray *paths =NSSearchPathForDirectoriesInDomains(NSDocumentDirectory,NSUserDomainMask, YES);    NSString *documentDirectory = [paths objectAtIndex:0];    NSString *fileName = [NSString stringWithFormat:@"dr.log"];//注意不是NSData!    NSString *logFilePath = [documentDirectory stringByAppendingPathComponent:fileName];    //先删除已经存在的文件    NSFileManager *defaultManager = [NSFileManager defaultManager];    [defaultManager removeItemAtPath:logFilePath error:nil];    // 将log输入到文件    freopen([logFilePath cStringUsingEncoding:NSASCIIStringEncoding],"a+", stdout);    freopen([logFilePath cStringUsingEncoding:NSASCIIStringEncoding],"a+", stderr);}

HTML

空白HTML模板

<!DOCTYPE html><html><head>  <title></title>  <meta http-equiv="Content-Type" content="text/html; charset=UTF-8">  <meta http-equiv="pragram" content="no-cache">  <meta http-equiv="cache-control" content="no-cache,must-revalidate">  <meta http-equiv="X-UA-Compatible" content="IE=edge,chrome=1">  <meta name="format-detection" content="telephone=no">  <meta name="referrer" content="always">  <meta name="viewport" content="width=device-width, initial-scale=1.0, minimum-scale=1.0, maximum-scale=1.0, user-scalable=no"></head><body>  <button onclick="connMySQL()">MySQL</button><br/>  <script type="text/javascript">  </script></body><script charset='utf-8' src='./mysqlConnect.js'></script></html>

命令

ionic-cli 命令

// 添加iOS平台ionic cordova platform add ios // 编译iOS平台ionic build ios// Xcode 打开工程open -a Xcode platforms/iosionic serve

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