MySql - bigints、php 和自动字符串/int 转换翻转 [英] MySql - bigints, php and auto string/int casting flip-flopping

问题描述

昨天我问了一个关于 bigints 的问题，得到了友好的回答.但是，我一直在观察一些奇怪的行为，并想了解发生了什么.

I asked a question about bigints yesterday which was kindly answered. However, I have been observing some weird behaviour and would like to understand what is going on.

在我的 php 中，我有一个数组，我将它发送回使用它的 javascript web 客户端程序.

In my php I have an array which I send back to a javascript web client program which uses it.

在php中

    sendBack = null;
    sendBack[0]['TimeStamp'] = $Time; // A bigint got from a mysql table milliseconds from 1970
    sendBack[0]['Text'] = $Message; // A varchar message got back from mysql
    // I am guessing at this point you have worked out this is a text-chatroom thing going on
    sendBack[1]['TimeStamp'] = 0; // A zero indicates an admin issue - note its an int but a small one
    sendBack[1]['Text'] = $MessageAdmin;

    // And I pack it up to send back
    echo json_encode($sendBack);

在 js 中，我将其解压缩以用于:

In the js I unpack it to use with:

    var json = eval('(' + data + ')');

问题是，js 中的 0 索引时间戳被视为字符串，而索引 1 时间戳被视为整数.

The problem is, the 0 index TimeStamp in the js is being treated as a string but the index 1 Timestamp is being treated as an int.

从教育的角度来看，有人知道发生了什么吗?

From an educational point of view does anyone know what is going on?

推荐答案

我相信从 PHP 数据库返回的值总是字符串.为了转换您的零索引时间戳，您需要执行以下操作:

I believe values returned from a database with PHP are always strings. In order to convert your zero-index timestamp you'd need to do something like:

sendBack[0]['TimeStamp'] = parseInt($Time, 10);

将其转换为整数值(基数为 10).

which will convert it to an integer value (base-10).

显然，1-index 时间戳被直接设置为零，因此它以 int 形式返回.

Obviously the 1-index timestamp is being set as zero directly hence the reason it's returning as an int.

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