How to display alert message with '&' in asp.net c#?

it is Beacause the Value after & is considered as the second value as the Querystring are seprated By the "&"  just try this solution 

 

string encodedValue = Server.UrlEncode("File(" + test.Text + ") Uploaded Successfully");
Response.Redirect("example.aspx?message="+encodedValue ,false);

 

At the decoding side try this

  string message = Server.UrlDecode(Request.QueryString["message"].ToString());

 

 

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