Summary of how javascript calls front and back method instances

JS calls the background, the background calls the frontend, etc. Summary

1. Execute the function in the C# code in the javaScript function:

Method 1: 1. First establish A button writes the calling or processing content into Button1_Click in the background;

protected void Button1_Click(object sender, EventArgs e) 
{ 
this.TextBox1.Text = "voodooer"; 
}

2. It can be called like this in the foreground:

<input type="button" value="访问C#的方法" onclick=&#39;document.getElementById("Button1").click();&#39; />

Method 2: 1. The function is declared as public or protected

public string ss() 
{ 
return("voodooer"); 
}

2. Foreground calling method

<script language=javascript> 
var a = " <%=ss()%>"; 
alert(a); 
</script>

Method three: 1.

<!-- 
function __doPostBack(eventTarget, eventArgument) 
{ 
var theForm = document.Form1; //指runat=server的form 
theForm.__EVENTTARGET.value = eventTarget; 
theFrom.__EVENTARGUMENT.value = eventArgument; 
theForm.submit(); 
} 
--> 
</script> 
<input type="button" value="按钮" >

Method four:

<script language="javascript"> 
function SubmitKeyClick() 
{ 
if (event.keyCode == 13) 
{ 
event.cancelBubble = true; 
event.returnValue = false; 
document.all.FunName.value="你要调用的函数名"； 
document.form[0].submit(); 
} 
} 
</script> 
<INPUT type="text"> 
<input type="hidden" > 〈！--用来存储你要调用的函数 --〉

In .CS there are:

public Page_OnLoad() 
{ 
if (!Page.IsPost()) 
{ 
string strFunName=Request.Form["FunName"]!=null?Request.Form["FunName"]:""; 
//根据传回来的值决定调用哪个函数 
switch(strFunName) 
{ 
case "enter()": 
enter() ; //调用该函数 
break; 
case "其他": 
//调用其他函数 
break; 
default: 
//调用默认函数 
break; 
} 
} 
} 
public void enter() 
{ 
//……比如计算某值 
}

2. How to access C# variables in JavaScript?

The answer is as follows:

Method 1: 1. Access through hidden fields on the page

Method 2: 1. If PUBLIC STRING N is defined in the background; the format for referencing this variable in the front-end js is' 'or "+ +"

Method 3: 1. Or you can register a script on the page after assigning values ​​to server-side variables

" <script language=&#39;javascript&#39;>var temp=" + tmp + " </script>"

tmp It is a background variable, and then you can directly access temp in js to get the value.

3. How to access existing variables of JavaScript in C#?

The answer is as follows:

Method 1: 1. Use static text control to hide the field in the front desk and change the js variable Write the value into it;

2. Use request["id"] in the background to get the value;

Method 2: You can use cookie or session

4. How to use C# Access JavaScript functions in?

The answer is as follows:

Execute javaScript functions in c# code:

Method 1: 1. Page.RegisterStartupScript("ggg"," <script>"); <br/><br/>Method 2: Use Literal class, then </script>

private void Button2_Click(object sender, System.EventArgs e) 
{ 
string str; 
str=" <script language=&#39;javascript&#39;>"; 
str+="selectRange()"; 
str+=" </script>"; 
//Literal1.Visible=true; 
Literal1.Text=str; 
}

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