Home >php教程 >php手册 >php等号(==)与全等(===)

php等号(==)与全等(===)

WBOY
WBOYOriginal
2016-06-21 08:47:481247browse


require_once "Person.php";
header("content-type:text/html;charset=utf-8");
$person001=new Person("wuxifu", 110);
$person002=new Person("wuxifu", 110);
$person003=$person001;
//全等(===)判断首先要数据类型要一样,数据类型不一样就为false
//(1)是同一数据类型后,如果是对象(如果是同一对象则为true否者为false)

echo "
person001与person002不是同一对象的情况下,不全等*************
";
if($person001===$person002)
{
echo "person001===person002是同一对象";
}else
{
echo "person001!==person002不是同一对象";

}
echo "
person001与person003是同一对象的情况下,全等**************
";
if($person001===$person003)
{
echo "person001===person003是同一对象";
}else
{
echo "person001!==person003不是同一对象";

}
//(2)是同一数据类型后,如果是数组(如果内容一样则为true否者为false)
$array=array(110,120,130);
$array2=array(110,120,130);
$array3=$array;
echo "

array与array2不是同一数组,但内容一样,全等*************
";
if($array===$array2)
{
echo "array===array2";
}else
{
echo "array!==array2";
}
echo "
array与array3不是同一数组,但内容一样,全等************************
";
if($array===$array3)
{
echo "array===array3";
}else
{
echo "array!==array3";
}
echo "
array与array3不是同一数组,内容也不一样,不全等***********************
";
$array3[0]=0;
if($array===$array3)
{
echo "array===array3";
}else
{
echo "array!==array3";
}
echo "
";
//(3)是同一数据类型后,如果是四种标量类型(boolean,integer,float,string),值一样则为true否者为false
echo "
是同一数据类型后,如果是四种标量类型(boolean,integer,float,string),值一样则为true否者为false
";

$nums=110;
$nums2=120;
$nums3=110;
if($nums===$nums2)
{
echo "nums===nums2值一样";
}else
{
echo "nums!==nums2值不一样";

}
echo "
";
if($nums===$nums3)
{
echo "nums===nums3值一样";
}else
{
echo "nums!==nums3值不一样";

}
//(4)不是同一种数据类型,则为false
echo "

不是同一种类型为false不全等********************************
";
if($nums===true)
{
echo "nums===true";
}else
{
echo "nums!==true";

}
echo "
";
if($person001===true)
{
echo "person001===true";
}else
{
echo "person001!==true";

}

?>




*************************************************************


require_once "Person.php";
header("content-type:text/html;charset=utf-8");
$person001=new Person("wuxifu", 110);
$person002=new Person("wuxifu", 110);
$person003=$person001;
//等(==)判断首先要数据类型一样不,不一样的话,如果等号有一边是boolean类型则另一边转换成boolean类型,否则等号右边的会强制转换成左边的数据类型
//(1)是同一数据类型后,如果是对象(只要两对象的内容一样则为true否者为false)
echo "
person001与person002不是同一对象的情况下,但内容一样等*************
";

if($person001==$person002)
{
echo "person001==person002内容一样";
}else
{
echo "person001!=person002内容不一样";

}
echo "
person001与person003是同一对象的情况下(内容一样),等**************
";

if($person001==$person003)
{
echo "person001==person003是同一对象";
}else
{
echo "person001!=person003不是同一对象";

}
//(2)是同一数据类型后,如果是数组(如果内容一样则为true否者为false)
$array=array(110,120,130);
$array2=array(110,120,130);
$array3=$array;
echo "

array与array2不是同一数组,但内容一样,等*************
";

if($array==$array2)
{
echo "array==array2";
}else
{
echo "array!=array2";
}
echo "
array与array3不是同一数组,但内容一样,等************************
";

if($array==$array3)
{
echo "array==array3";
}else
{
echo "array!=array3";
}
echo "
array与array3不是同一数组,内容也不一样,不等***********************
";

$array3[0]=0;
if($array==$array3)
{
echo "array===array3";
}else
{
echo "array!==array3";
}
echo "
";
//(3)是同一数据类型后,如果是四种标量类型(boolean,integer,float,string),值一样则为true否者为false
echo "
是同一数据类型后,如果是四种标量类型(boolean,integer,float,string),值一样则为true否者为false
";

$nums=110;
$nums2=120;
$nums3=110;
if($nums==$nums2)
{
echo "nums==nums2值一样";
}else
{
echo "nums!==nums2值不一样";

}
echo "
";
if($nums==$nums3)
{
echo "nums==nums3值一样";
}else
{
echo "nums!=nums3值不一样";

}
//(4)不是同一种数据类型,如果等号某一边有boolean类型的值,则将另一边转换成boolean类型,否则等号右边的会转成等号左边的数据类型
echo "

不是同一种数据类型,如果等号某一边有boolean类型的值,则将另一边转换成boolean类型,否则等号右边的会转成等号左边的数据类型********************************
";

if($nums==true)
{
echo "nums==true";
}else
{
echo "nums!=true";

}
echo "
";
if($person001==true)
{
echo "person001==true";
}else
{
echo "person001!=true";

}
echo "
";
if(true==$nums)
{
echo "true==nums";
}else
{
echo "true!=nums";

}
echo "
";
if(true==$person001)
{
echo "true==person001";
}else
{
echo "true!=person001";

}
echo "
";
if($array==$person001)
{
echo "array==person001";
}else
{
echo "array!=person001";

}
echo "
";
if($array==true)
{
echo "array==true";
}else
{
echo "array!=true";

}

?>



Statement:
The content of this article is voluntarily contributed by netizens, and the copyright belongs to the original author. This site does not assume corresponding legal responsibility. If you find any content suspected of plagiarism or infringement, please contact admin@php.cn