Question

tp5框架下用composer安装验证码类库报错问题

Using version ^2.0 for topthink/think-captcha./composer.json has been updatedLoading composer repositories with package informationUpdating dependencies (including require-dev)Your requirements could not be resolved to an installable set of packages. Problem 1 - topthink/think-captcha v2.0.2 requires topthink/framework 5.1.* -> satisfiable by topthink/framework[5.1.x-dev, v5.1-beta.1, v5.1-rc.1, v5.1-rc.2, v5.1-rc.3, v5.1.0, v5.1.1, v5.1.2, v5.1.3, v5.1.4, v5.1.5] but these conflict with your requirements or minimum-stability. - topthink/think-captcha v2.0.1 requires topthink/framework 5.1.x-dev -> satisfiable by topthink/framework[5.1.x-dev] but these conflict with your requirements or minimum-stability. - topthink/think-captcha v2.0 requires topthink/framework 5.1.x-dev -> satisfiable by topthink/framework[5.1.x-dev] but these conflict with your requirements or minimum-stability. - Installation request for topthink/think-captcha ^2.0 -> satisfiable by topthink/think-captcha[v2.0, v2.0.1, v2.0.2].Installation failed, reverting ./composer.json to its original content.composer require topthink/think-captcha //安装扩展包验证码类库的代码以上就是报错提示，我百度和翻译后都没解决到问题！虚心请教
什么情况，我换行了怎么没效果了，看不清的麻烦追问一下，抱歉了。

Answer 1

利用TP5框架生成验证码需要安装captcha扩展，可以利用composer来安装：
　　　composer require topthink/think-captcha
　　
　　安装完成之后会呈现如上的目录。captcha扩展安装完成之后，就可以进行下一步操作
　　配置comfig.php文件：
　　
　　在html文件需要验证码的地方输入{：captcha_img()}; 验证就生成完毕了。
　　效果预览
　　

2.如何刷新验证码
　　验证码有时候太模糊，用户希望切换下一张验证码，该如何操作呢？
　　验证的扩展和配置如上，需要修改html部分。

Answer 2

版本问题

安装1.*版本的扩展包 最新的2.0是用于5.1版本的，如下

composer require topthink/think-captcha=1.*

解决办法来源：网页链接