字符串相等原因
请教一下，为何PHP认为一下两个字符串是相等的？
if("03E-004611"=="36E-008026") echo '相等';
回复讨论(解决方案)
var_dump("03E-004611"=="36E-008026"); //bool(true)var_dump(03E-004611, 36E-008026); //float(0) float(0)var_dump("03E-004611"==="36E-008026"); //bool(false)由数字组成的串，在比较时会先转换为数值
请教一下，为何PHP认为一下两个字符串是相等的？
if("03E-004611"=="36E-008026") echo '相等';
楼上解释的还不是很完善，因为你使用的是双引号，而且你的是数字组成的，在双引号里是可以执行的，这个是php的一个特点，如果换成单引号那就不一样了
因为E是10的幕运算 "03E-004611"转换成符点数时已经无限接近0了,3*pow(10,-4611),达不到这么高的精度,所以就都是0了.
长知识了
请教一下，为何PHP认为一下两个字符串是相等的？
if("03E-004611"=="36E-008026") echo '相等';
楼上解释的还不是很完善，因为你使用的是双引号，而且你的是数字组成的，在双引号里是可以执行的，这个是php的一个特点，如果换成单引号那就不一样了
换成单引号结果也是一样吧
这与是否在单双引号内无关！
只是个对科学计数法的认知问题
你说 我有试过90A-904611与36E-008026，这两个字符串就不相等吖
其中 36E-008026 可视为科学计数法，而 90A-904611 不是
所以对这样的编号需要按字符串进行比较，而不是数值
涨姿势了 啊啊
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