ios - 检查NSString的长度

Question

我认为在检查字符串长度时遇到错误。自从我为新的iOS 6更新了Xcode以来，这只是最近的事情。

这就是我检查我的NSStrings长度的方式

if ([manuIdString length] != 0) {

然后，当线程点击此..在manuIdString中有一个明确的值，但出现此错误。

2012-10-11 10:01:57.715 paranioa[8619:907] -[__NSCFNumber length]: unrecognized selector sent to instance 0x1f83ed60
2012-10-11 10:01:57.717 paranioa[8619:907] *** Terminating app due to uncaught exception 'NSInvalidArgumentException', reason: '-[__NSCFNumber length]: unrecognized selector sent to instance 0x1f83ed60'
*** First throw call stack:
(0x36b5b2a3 0x34e6b97f 0x36b5ee07 0x36b5d531 0x36ab4f68 0x25949 0x37f170ad 0x37f17135 0x37f170ad 0x37f1705f 0x37f1703d 0x37f168f3 0x37f16de9 0x37e3f5f9 0x37e2c809 0x37e2c123 0x36fdf5a3 0x36fdf1d3 0x36b30173 0x36b30117 0x36b2ef99 0x36aa1ebd 0x36aa1d49 0x36fde2eb 0x37e80301 0x1fb41 0x3b58cb20)
libc++abi.dylib: terminate called throwing an exception

任何帮助将不胜感激

Answer 1

manuIdString不是NSString。您不小心为其分配了NSNumber。