如果几个方法函数的逻辑顺序错了

如果用错方法函数或是用少了,如果几个方法函数的逻辑顺序错了,很可能就是一个漏洞,而且不容易找出来。纠结啊~

上网找找看哪位高人有总结出相关的结论出来,果然有!不过似乎不是很全面,我在这里稍完善了一下,仅供参考。复制代码 代码如下: // 判断 0 与
”、null、empty、false 之间的关系 $a = 0; echo “0 与 ”、
empty、null、false 之间的关系:”; if{ echo “0 == ”;”; }else{ echo “0 !=
”;”; } if{ echo “trim == ”;”; }else{ echo “trim != ”;”; } if{ echo
“strval == ”;”; }else{ echo “strval != ”;”; } if{ echo “0 === ”;”;
}else{ echo “0 !=== ”;”; } if{ echo “0 is empty;”; }else{ echo “0 is
not empty;”; } if{ echo “0 is null;”; }else{ echo “0 is not null;”; }
if{ echo “0 is numeric;”; }else{ echo “0 is not numeric;”; } if{ echo “0
is string;”; }else{ echo “0 is not string;”; } if{ echo “0 is false;”;
}else{ echo “0 is not false;”; } // 判断 ” 和 0、null、empty、false
之间的关系 $a = ”; echo “” 和 0、empty、null、false 之间的关系:”; if{
echo “” == 0;”; }else{ echo “” != 0;”; } if{ echo “intval == 0;”;
}else{ echo “intval != 0;”; } if{ echo “” is empty;”; }else{ echo “”
is not empty;”; } if{ echo “” is null;”; }else{ echo “” is not null;”;
} if{ echo “” is numeric;”; }else{ echo “” is not numeric;”; } if{
echo “” is string;”; }else{ echo “” is not string;”; } if{ echo “” is
false;”; }else{ echo “” is not false;”; } // 判断 null 和
”、0、empty、false 之间的关系 $a = null; echo “null 和
”、0、empty、false 之间的关系:”; if{ echo “null == ”;”; }else{ echo
“null != ”;”; } if{ echo “null == 0;”; }else{ echo “null != 0;”; } if{
echo “null === ”;”; }else{ echo “null !=== ”;”; } if{ echo “null ===
0;”; }else{ echo “null !=== 0;”; } if{ echo “strval == ”;”; }else{ echo
“strval != ”;”; } if{ echo “intval == 0;”; }else{ echo “intval != 0;”;
} if{ echo “null is empty;”; }else{ echo “null is not empty;”; } if{
echo “null is numeric;”; }else{ echo “null is not numeric;”; } if{ echo
“null is string;”; }else{ echo “null is not string;”; } if{ echo “null
is false;”; }else{ echo “null is not false;”; } echo “”; 输出的结果是:

我想根据输出结果都可以清楚了解决空字符串、0、null、empty和false之间的大概关系,在开发过程中灵活运用上述代码里的方法,加上良好的逻辑,基本上应该是不会出现问题的了。点击下载相关源代码