错误信息
RangeError: {0} is not a valid code point (Firefox) RangeError: Invalid code point {0} (Chrome)
错误类型
什么地方出错了?
String.fromCodePoint()
这个方法只能接受有效的码位(code point) 。
码位( code point)是组成码空间(或代码页)的数值,范围是 0 到 0x10FFFF。
NaN
,负整数(-1),非整数(3.14),或编号大于0x10FFFF (1114111) 的字符,无法使用该方法。
范例
无效的例子
String.fromCodePoint('_'); // RangeError String.fromCodePoint(Infinity); // RangeError String.fromCodePoint(-1); // RangeError String.fromCodePoint(3.14); // RangeError String.fromCodePoint(3e-2); // RangeError String.fromCodePoint(NaN); // RangeError
有效的例子
String.fromCodePoint(42); // "*" String.fromCodePoint(65, 90); // "AZ" String.fromCodePoint(0x404); // "\u0404" String.fromCodePoint(0x2F804); // "\uD87E\uDC04" String.fromCodePoint(194564); // "\uD87E\uDC04" String.fromCodePoint(0x1D306, 0x61, 0x1D307) // "\uD834\uDF06a\uD834\uDF07"