ASP.NET

string a = "hello";
string b = "world!!!";
string str = string.Format("\"{0}\"\"{1}\"", a, b);

string a="\"a\"";
string b = "\"b\"";
string c = a + b;
string d= "c="+c;
Response.Write(d);

string a="\"a\"";
string b = "\"b\"";
string c = a + b;
string d= "c="+c;
Response.Write(d);

protected void Page_PreInit(object sender, EventArgs e)
   {
 if (Request.Params["PageName1"] != null)
       {
           this.MasterPageFile = "~/MasterPages/PageName1.master";
       }
       else if (Request.Params["PageName2"] != null)
       {
           this.MasterPageFile = "~/MasterPages/PageName2.master";
       }
       else
       {
           this.MasterPageFile = "~/MasterPages/Default.master";
       }