JSON消息
本节示例可以参考示例文件"CaseStudy\WebViewer\接收消息.Table"的窗口"JSON消息"。
本示例的任务是演示如何在前端页面向Foxtable发送JSON消息。
1、窗口的AfterLoad事件代码：
'''Async
Dim
wv
As
WebViewer = e.Form.Controls("WebViewer1").WebViewer
Await
wv.EnsureCoreWebView2Async(Nothing)
'初始化浏览器
'定义测试页面
Dim
html
As
String
=
<![CDATA[
<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8" />
<title>JSON数据通信</title>
</head>
<body>
<h3>发送JSON格式用户信息</h3>
<button onclick="sendUserInfo()">发送用户信息</button>
<script>
function sendUserInfo() {
//
定义JSON对象
const user = {
Name: "张三",
Age: 25,
IsVIP: true
};
//
发送对象（会自动序列化为JSON字符串）
chrome.webview.postMessage(user);
}
</script>
</body>
</html>
]]>.Value
wv.CoreWebView2.NavigateToString(html)
'打开测试页面
2、WebMessageReceived事件代码：
Dim
user
As
JObject = JsonConvert.DeserializeObject(e.WebMessageAsJson)
Dim
name
As
String
= user("Name")
Dim
age
As
Integer
= user("Age")
Dim
isVip
As
Boolean
= user("IsVIP")
Dim
info
As
String
=
"姓名:"
& name & vbCrLf &
"年龄:"
& age & vbCrLf &
"VIP:"
& isVip
MessageBox.Show("收到前端发来的消息:"
& vbCrLf & info,"提示",MessageBoxButtons.OK,MessageBoxIcon.Information)
也可以不用解析为JObject，用ExpandoObject，代码如下：
Dim
user
As
Object
= JsonConvert.DeserializeObject(Of
ExpandoObject)(e.WebMessageAsJson)
Dim
name
As
String
= user.Name
Dim
age
As
Integer
= user.Age
Dim
isVip
As
Boolean
= user.IsVIP
Dim
info
As
String
=
"姓名:"
& name & vbCrLf &
"年龄:"
& age & vbCrLf &
"VIP:"
& isVip
MessageBox.Show("收到前端发来的消息:"
& vbCrLf & info,"提示",MessageBoxButtons.OK,MessageBoxIcon.Information)
我个人更喜欢用ExpandoObject，因为用原点符号访问数据更方便。