Question

我是iPhone的初学者，我得到了如下所示的运行时错误。当我在getColor方法中传递对象“textView.textColor = [self getColor：appDelegate.pickcolor];”我收到了错误

由于未捕获的异常'NSRangeException'而终止应用程序，原因：' - [__ NSCFConstantString substringWithRange：]：范围或索引越界'

- (UIColor *) getColor: (NSString *) hexColor
{
    //NSLog(@"Calling Getcolor..");
    unsigned int red, green, blue;
    NSRange range;
    range.length = 2;

    range.location = 0; 
    [[NSScanner scannerWithString:[hexColor substringWithRange:range]] scanHexInt:&red];
    //NSLog(@"\n\tRed :%d\n",red);
    range.location = 2; 
    [[NSScanner scannerWithString:[hexColor substringWithRange:range]] scanHexInt:&green];
    //NSLog(@"\n\tgreen :%d\n",green);
    range.location = 4; 
    [[NSScanner scannerWithString:[hexColor substringWithRange:range]] scanHexInt:&blue];   
    //NSLog(@"\n\tblue :%d\n",blue);
    return [UIColor colorWithRed:(float)(red/255.0f) green:(float)(green/255.0f) blue:(float)(blue/255.0f) alpha:1.0f];
}

提出任何建议和解决方案

Answer 1

也许十六进制字符串不是6个字符或更多？

您可以在方法开头添加健全性检查以捕获该方案。

- (UIColor *) getColor: (NSString *) hexColor
{
    if ([hexColor length] < 6)
        return nil;

    // ...
}

如何解决Range或index越界的运行时错误？

1 个答案: