字符串，那位朋友解释一下
xxx= "scrollamount=     ' "   +   txt1.Text   +   " ' ";
正确
string   UserDirectory   =   "TestFileId "

FileUploadImage.SaveAs(System.Web.HttpContext.Current.Request.MapPath(   UserDirectory   +     "/Images/ ")   +   FileUploadImage.FileName);

如何让UserDirectory   +     "/Images/ "   连起来   解释一下asp.net   的字符串
+   STR   +
' "   +   STR   +   " '
" '+   str   +   ' "
等，为什么这样
以前曾想明白过，几年不编程了，忘了
谢谢

------解决方案--------------------
不明白你想问什么?
------解决方案--------------------
string a= "1 ";
string b= "2 ";
string c=a+b;
string d= "1 "+b;
------解决方案--------------------
+ STR +
//比如str1= "sdf " + STR + "sdkj ";
' " + STR + " '
//比如strsql = "update usersheet set username= ' " + STR + " ',userpass= ' " + Pass + " ' ";

" '+ str + ' "
//这个似乎没有