javascript - 用于从变换矩阵中选择元素的正则表达式

Question

我有以下方式给出的样式转换字符串：

matrix(0.312321, -0.949977, 0.949977, 0.312321, 0, 0)

如何形成包含该矩阵元素的数组？任何提示如何为此编写正则表达式？

Answer 1

我会这样做...

// original string follows exactly this pattern (no spaces at front or back for example)
var string = "matrix(0.312321, -0.949977, 0.949977, 0.312321, 0, 0)";

// firstly replace one or more (+) word characters (\w) followed by `(` at the start (^) with a `[`
// then replace the `)` at the end with `]`
var modified = string.replace(/^\w+\(/,"[").replace(/\)$/,"]");
// this will leave you with a string: "[0.312321, -0.949977, 0.949977, 0.312321, 0, 0]"

// then parse the new string (in the JSON encoded form of an array) as JSON into a variable
var array = JSON.parse(modified)

// check it is correct
console.log(array)

Answer 2

这是一种方法。用正则表达式解析出数字部分，然后使用split()方法：

var s = "matrix(0.312321, -0.949977, 0.949977, 0.312321, 0, 0)";
s.match(/[0-9., -]+/)[0].split(", "); // results in ["0.312321", "-0.949977", "0.949977", "0.312321", "0", "0"]

Answer 3

试试这个：

/^matrix\(([+\-\d.]+), ([+\-\d.]+), ([+\-\d.]+), ([+\-\d.]+), ([+\-\d.]+), ([+\-\d.]+)\)$/
    .exec(str).slice(1);

演示

Answer 4

可能是这样的：

var string = "matrix(0.312321, -0.949977, 0.949977, 0.312321, 0, 0)";

var array = string.replace(/^.*\((.*)\)$/g, "$1").split(/, +/);

请注意，通过这种方式，数组将包含字符串。如果你想要实数，一个简单的方法是：

array = array.map(Number);

你的 js 引擎需要支持map或者有一个 shim （当然你也可以手动转换）。