当我将NSString转换为float时出现问题

Question

将NSString转换为float时出现问题。我没有价值，但为什么呢？

NSString *polylineStr = @"51.351305,-0.024239;51.374855,-0.092412";
NSArray *strPolylineArr = [polylineStr componentsSeparatedByString:@";"];
for ( NSString *str in strPolylineArr) {

    NSArray *arr = [str componentsSeparatedByString:@","];
    NSString *firstString = [arr firstObject];
    NSLog(@"__str %@ float %f", [arr firstObject], [firstString floatValue]);
}

我的输出是

__str 51.351305 float 0.000000
__str 51.374855 float 51.374855

我发现第一个字符串出错了。

Answer 1

你的字符串中的HI有些字符添加：''你看不到复制字符在单引号上或使用下面的代码：

NSString *polylineStr = [NSString stringWithFormat:@"51.351305,-0.024239;51.374855,-0.092412"];
    NSArray *strPolylineArr = [polylineStr componentsSeparatedByString:@";"];
    for ( NSString *str in strPolylineArr) {

        NSArray *arr = [str componentsSeparatedByString:@","];
        NSString *firstString = [arr firstObject];
        NSLog(@"__str %@ float %f", [arr firstObject], [firstString floatValue]);
    }