do Postback in Javascript [ASP.NET]

dopostback javascript
In this post we will see how to postback page in ASP.NET from the client side using JavaScript. In some cases we need to postback page from client side i.e. by using JavaScript.
We can use __doPostBack() to postback page from client script using JavaScript.Or we can use Page.GetPostBackEventReference() to do postback from JavaScript. When we use Page.GetPostBackEventReference() it internally get converted to __doPostBack().

Sample that shows how to do postback from JavaScript [ASP.NET, C#]:

< input type="button" id="BaseButton1" onclick="submitPage()" value="OK"/>

Now after clicking on button it will call JavaScript function that will do the postback and then in page load we will capture and perform the operation that is needed.In code behind we use Request[ "__EVENTARGUMENT"] to get the request so that we can perform some operation on that event argument.So below is JavaScript function that uses Page.GetPostBackEventReference() and do the postback from Javascript.

function submitpage() 
  // trigger postback from JavaScript
   <%= this.Page.GetPostBackEventReference(this,"Delete")%> 

GetPostBackEventReference Here “this” parameter in Page.GetPostBackEventReference(this, “Delete”) is the controls id and referred to as __EVENTTARGET and accessed using Request[“__EVENTTARGET”] in code behind to determine which control caused postback from JavaScript.And “Delete” is __EVENTARGUMENT and accessed using Request[ "__EVENTARGUMENT"] in code behind.

So now in code behind we can check for Request[ "__EVENTARGUMENT"] and perform some operations based on that condition like:

protected void Page_Load(object sender, EventArgs e) 
string eventArg = Request["__EVENTARGUMENT"]; 
if (!String.IsNullOrEmpty(eventArg)) 
 if(eventArg == "Delete")

private void DeleteRecords() 
 //Do something


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