Asp.net frontend JavaScript and background C # mutual call

Execute functions in C # code in JavaScript Functions:

Method 1: 1. Create a button to write the called or processed content to button_click in the background;

2. Write a JS function on the front-end with the content document. getelementbyid ("btn1"). Click ();

3. Call JS functions on the frontend or backend to stimulate the click event, which is equivalent to accessing the C # function in the background;

Method 2: 1. function declaration is public

Background code (change public to protected)

The following is a reference clip: Public String SS () { Return (""); }

2. can be called in HTML

Foreground script

The following is a reference clip: <Script language = JavaScript> VaR A = "<% = SS () %> "; Alert (); </SCRIPT>

Method 3: 1. <! -- Inject script filtered -->

The following is a reference clip: , <Script language = "JavaScript"> <! -- Function _ dopostback (eventtarget, eventargument) { VaR theform = Document. form1; // indicates the form of runat = server. Theform. _ eventtarget. value = eventtarget; Thefrom. _ eventargument. value = eventargument; Theform. Submit (); } --> </SCRIPT> <Input id = "button1" type = "button" name = "button1" value = "button" onclick = "javascript :__ dopostback ('button1','') ">

Method 4:

The following is a reference clip: <Script language = "JavaScript"> Function submitkeyclick () { If (event. keycode = 13) { Event. cancelbubble = true; Event. returnvalue = false; Document. All. funname. value = "Name of the function you want to call "; Document. Form [0]. Submit (); } } </SCRIPT> <Input onkeypress = "submitkeyclick ()" id = "AAA" type = "text"> <Input type = "hidden" name = "funname"> <〈! -- Used to store the function you want to call --> --〉

In. CS, there are:

The following is a reference clip: Public page_onload () { If (! Page. ispost ()) { String strfunname = request. Form ["funname"]! = NULL? Request. Form ["funname"]: ""; // Determine which function to call based on the value returned Switch (strfunname) { Case "Enter ()": Enter (); // call this function Break; Case "Others ": // Call other functions Break; Default: // Call the default Function Break; } } } Public void enter () { //...... For example, calculating a value }

　　Question 2. How to access the C # variable in JavaScript?

　　The answer is as follows:

Method 1: 1. Hide domain access on the page

The following is a reference clip: <Input id = "XX" type = "hidden" runat = "server">

Method 2: 1. If the backend defines public string N, the format of the variable referenced in front-end JS is ''or" ++"

Method 3: 1.ServerRegister a script on the page after the terminal variable value is assigned.

The following is a reference clip: "<Script language = 'javascript '> var temp =" + TMP + "</SCRIPT>"

TMP is the background variable, and then you can directly access temp in JS to obtain the value.

　　Question 3. How to access existing JavaScript variables in C?

　　The answer is as follows:

Method 1: 1. the foreground uses static text controls to hide the field and write the JS variable value into it. 2. The background uses request ["ID"] to obtain the value;

Method 2: cookie or session can be used

　　Question 4. How to access JavaScript Functions in C?

　　The answer is as follows:

C # execute JavaScript Functions in the Code:

Method 1: 1,

The following is a reference clip: Page. registerstartupscript ("ggg ","");

Method 2: Use the literal class and

The following is a reference clip: Private void button2_click (Object sender, system. eventargs E) { String STR; STR = ""; // Literal1.visible = true; Literal1.text = STR; }