Several ways of string substitution in asp.net array _ practical Tips

Copy Code code as follows:

Method 1
protected void Page_Load (object sender, EventArgs e)
{
if (! Page.IsPostBack)
{
Replacestr ();
}
}
public void Replacestr ()
{
ArrayList myarray = new ArrayList ();
Myarray.add ("123");
Myarray.add ("AAA");
if (Myarray.contains ("AAA"))
{
Myarray.remove ("AAA");
Myarray.add ("BBB");
}
for (int i = 0; I <= myarray.count-1; i++)
{
Response.Write (Myarray[i]. ToString ());
}
}

Method 2
protected void Page_Load (object sender, EventArgs e)
{
if (! Page.IsPostBack)
{
Replacestr ();
}
}
public void Replacestr ()
{
string [] tm = new string[] {"123", "AAA"};
for (int i = 0; I < TM. Length; i++)
{
if (tm[i). ToString () = "AAA")
{
Tm[i]=tm[i]. Replace ("AAA", "BBB");

}
}
for (int i = 0; I <= TM. Length-1; i++)
{
Response.Write (Tm[i]. ToString ());
}
}
Method 3
protected void Page_Load (object sender, EventArgs e)
{
if (! Page.IsPostBack)
{
String[] TM = new string[] {"123", "AAA"};
String Array=replacevalue (tm, "AAA", "BBB", ",");
Response.Write (Array);
}
}
public static string Replacevalue (String[] Item, String OLDSV, String Newsv, string separator)
{
if (item = NULL) return string. Empty;
StringBuilder sb = new StringBuilder ();
foreach (string s in Item)
{
if (s = = OLDSV)
{
Sb. Append (NEWSV);
Sb. Append (separator);
}
Else
{
Sb. Append (s);
Sb. Append (separator);
}
}
String returnstr = sb. ToString ();
Returnstr = (returnstr. EndsWith (separator))? Returnstr. Substring (0, Returnstr. LENGTH-1): Returnstr;
return returnstr;
}