C# - find the position of a string inside a predefined string array -

i have predefined string array letters a q :

string[] skippedareasarray = new string[] {"a", "b", "c", "d", "e", "f", "g",             "h", "i", "j", "k", "l", "m", "n", "o", "p", "q"}; 

in textbox inside windows form user can enter skippedareas this: a,b,c,d... there validations , restrictions use letters , commas input guaranteed in format.

what taking user input , populate string array:

string[] skippedareasfromform = new string[17]; ... skippedareasfromform = (txtskippedareas.text).split(','); 

now comes tricky part i'm seeking assistance. user must enter number of areas example - 3. mean working a, b, , c. if number of areas 2 can use a , b if number of areas 4 a, b, c , d available , on.

what need check if in array skippedareasfromform populated user input there area doesn't match above criteria.

what mean in terms of coding - need take every element skippedareasfromform, take it's integer value predefined skippedareasarray , see if value equal or greater (>=) of value entered `number of areas. if there area outside scope of selected number error should shown.

what have right :

foreach (string tempareavalue in skippedareasfromform)                 {                     (int = 0; < skippedareasarray.length; i++)                     {                         if (tempareavalue == skippedareasarray[i])                         {                             if ((i + 1) > entity.areascnt)                             {                                 messagebox.show("you must use areas within number of areas scope!", "error", messageboxbuttons.ok, messageboxicon.error);                                 txtskippedareas.focus();                                 return false;                             }                         }                     }                 } 

for few test made works. first - @ least me seems on complicated. second - i'm not sure algorithm working need or i'm having correct results luck. third - i'm coding c# 2months , seems me excellent candidate linq expression - think better using linq , appreciate in transformation.

i think you're looking indexof:

int index = skippedareasarray.indexof(tempareavalue); if (index >= entity.areascnt) {     ... } 

(you might want check index being -1, occur if element wasn't in list @ all. also, consider duplicates - can user enter a, a, a?)