Form Verification Using Javascript

[emmaclarke]

Actually the alert message shows because inputting "MK16" == [0]=="M" && [1] == "K" && [2] == "1".So I need:[0] == M && [1] == K && [2] == 1,2,3,4,5,6,7,8,9 OR [2] == 1 && [3] == 0 (11,12,13,14,15,17,19) OR [2] ==7 && [3] == 7.I did try this but the OR || statements didn't work - the postcode should be MK1-15, MK17, MK19 or MK77.

//conditions on beginning of the postcode to receive a special gift message, verifying each array element in the string for the position of the postcode								if ((((((text[0] == "M" || text[0] == "m") && (text[1] == "K" || text[1] == "k") && (text[2] == "1" || text[2] == "2" || text[2] == "3" || text[2] == "4" || text[2] == "5" || text[2] == "6" || text[2] == "7" || text[2] == "8" || text[2] == "9") || (text[2] == "1" && text[3] == "0" || text[2] == "1" && text[3] == "1" || text[2]== "1" && text[3] == "2" || text[2] == "1" && text[3] == "3" || text[2] == "1" && text[3] == "4" || text[2] == "1" && text[3] == "5" || text[2] == "1" && text[3] == "7" || text[2] == "1" && text[3] == "9") || (text[2] == "7" && text[3] == "7")))))) {								alert("you will receive a special gift");								}

The OR statements between the third brackets onward doesn't seem to work.

[emmaclarke]

It still hits the same condition == [0] = M [1] = K [2] = 1 so:text[2] == "1" && text[3] == " " should by pass this so that MK1 is not the same as MK16 since the condition was just checking the first 3 chars. i.e. MK1 is true in the case of MK1 and MK16.I will see if this works.

[Ingolme]

These || and && are so accumulated that it's getting easy to make mistakes in any point.A regular expression should do the job

// Do not split the text into an arrayvar reg = /^MK(1|2|3|4|5|6|7|8|9|10|11|12|13|14|15|17|19|77)\D/;/**** In english: MK followed by either of those numbers,*** making sure that there are no more digits than those required for the condition*/if(reg.test(text)) {  alert("you will receive a special gift");}