@ort-fe/react18-verify-code
Version:
基于React和canvas的验证码
84 lines (83 loc) • 3.51 kB
JavaScript
import React, { useRef, useEffect, useCallback, forwardRef, useImperativeHandle } from 'react';
import { originalCharacter, randomColor, randomNum } from './utils';
import isFunction from 'lodash/isFunction';
import cs from 'classnames';
var Captcha = forwardRef(function (_a, ref) {
var _b = _a.height, height = _b === void 0 ? 40 : _b, _c = _a.width, width = _c === void 0 ? 100 : _c, _d = _a.bgColor, bgColor = _d === void 0 ? '#DFF0D8' : _d, _e = _a.charNum, charNum = _e === void 0 ? 4 : _e, _f = _a.fontSize, fontSize = _f === void 0 ? 25 : _f, onChange = _a.onChange, onClick = _a.onClick, className = _a.className, onRef = _a.onRef, _g = _a.code, code = _g === void 0 ? '' : _g;
var canvas = useRef(null);
useEffect(function () {
onRef && onRef(canvas);
}, []);
useImperativeHandle(ref, function () { return ({
refresh: function () {
canvas.current.click();
},
}); });
// 生成原始的数据
var generateSourceCode = useCallback(function () {
var array = [];
if (code) {
return code.split('');
}
for (var i = 0; i < charNum; i++) {
var temp = originalCharacter[randomNum(0, originalCharacter.length - 1)];
array.push(temp);
}
return array;
}, [code, charNum]);
var generateCaptcha = useCallback(function () {
var checkCode = '';
if (canvas.current) {
var ctx = canvas.current.getContext('2d');
if (ctx) {
ctx.clearRect(0, 0, width, height);
ctx.beginPath();
ctx.fillStyle = bgColor;
ctx.fillRect(0, 0, width, height);
var sourceCode = generateSourceCode();
for (var i = 0; i < sourceCode.length; i++) {
var charGap = Math.round(width / charNum);
var offset = Math.round(charGap / 2) - 6;
var code_1 = sourceCode[i];
checkCode += code_1;
ctx.save();
ctx.beginPath();
ctx.fillStyle = 'white';
ctx.strokeStyle = randomColor();
ctx.font = fontSize + "px serif";
ctx.rotate((Math.PI / 180) * randomNum(-5, 5));
ctx.strokeText(code_1, offset + i * charGap, height / 2 + 8);
ctx.beginPath();
ctx.moveTo(randomNum(0, width), randomNum(0, height));
ctx.lineTo(randomNum(0, width), randomNum(0, height));
ctx.stroke();
ctx.restore();
}
return checkCode;
}
else {
return '';
}
}
else {
return '';
}
}, [code]);
var handleClick = useCallback(function () {
if (isFunction(onChange) && !code) {
var captcha = generateCaptcha();
onChange(captcha);
}
if (isFunction(onClick)) {
onClick();
}
}, [onChange, code]);
useEffect(function () {
var captcha = generateCaptcha();
if (isFunction(onChange) && !code) {
onChange(captcha);
}
}, [code]);
return (React.createElement("canvas", { style: { cursor: 'pointer' }, className: cs('react-captcha', className), onClick: handleClick, height: height, width: width, ref: canvas }));
});
export default Captcha;