ios - NSStringWithFormat 崩溃

Question

简单地说，下面的代码让我对它为什么会失败感到困惑。

// This line works
NSString * string = [NSString stringWithFormat:@"%lu",[[NSDate date] timeIntervalSince1970]];

// This line works
string = [NSString stringWithFormat:@"%@",@"somestring"];

// This line generates and EXEC_BAD_ACCESS error
string = [NSString stringWithFormat:@"%lu%@",[[NSDate date] timeIntervalSince1970],@"somestring"];

为什么？

Answer 1

返回的值[[NSDate date] timeIntervalSince1970]是您正在打印NSTimeInterval的类型 。替换为and 就可以了。typedef double NSTimeInterval;unsigned int@"%lu%@"@"%f%@"