javascript validation in asp.net 3.5

Question

i hv an aspx page in 3.5 so i want to validate 3 dropdownlist box for date with javascript.......then required field validate and email in correct format checkbox selection dropdown to validate for selection...with javascript....

Niradhip Chakraborty · Answer

For email validation you can use following javascript code: if (!isEmail(document.getElementById(txtEmail3).value)) { alert(Please Enter a Valid E-Mail Address in Shipping Address); document.getElementById(txtEmail3).focus(); return false; } //Note: txtEmail3 is the id of the textbox function isEmail(s){ if (s.search(/^[a-zA-Z][\w\.-]*[a-zA-Z0-9]@[a-zA-Z0-9][\w\.-]*[a-zA-Z0-9]\.[a-zA-Z][a-zA-Z\.]*[a-zA-Z]$/) == -1){ return false; } else{ return true; } } now If you have given as select date as the first index and if you are trying to enforce user to select valid date. you can try this: if(document.getElementById(cboDate).selectedIndex ==0) { alert(Please select the Security Question); return false; } //Note: cboDate is the id of the textbox I didnt understand the checkbox part.