StreamReader sr = new StreamReader("person.html", Encoding.UTF8);
string htmlBody = sr.ReadToEnd()
.Replace("{$报告日期$}", "2020年2月15日")
.Replace("{$体检卡号$}", "JD-202002150789123")
.Replace("{$单位名称$}", "种子公司")
.Replace("{$姓名$}", "张三丰")
.Replace("{$性别$}", "男")
.Replace("{$年龄$}", "70岁");
webBrowser1.DocumentText = htmlBody;
webBrowser1.ShowPrintPreviewDialog();