Validator Control Learn the first day

Today began to seriously learn validator control, draw the following experience:
1. With regard to the use of the RegularExpressionValidator control, I used this feature first because I wanted to use this control for email verification. I started by typing: [a-za-z0-9]@ [A-za-z0-9]{1,}, but the validation always fails, prompting for errors until I enter the format of x@x (or any of the characters in the x@*--* that represent me). Understand, the original in each [] after the length of the judgement, modified as follows [a-za-z0-9]{1,}@ [A-za-z0-9]{1,}, successfully passed the verification. Later looked up the data and found the use. {1,}@. {1,} more convenient (. On behalf of any character)
2. About the use of the ErrorMessage property. The error he prompts does not appear directly on the page, but rather passes the value of the property to ValidationSummary. The output of the page is then performed by ValidationSummary.
About the kinds of validator controls (there are 5 of them for validation, and one that provides a collection of validation results):
1. requiredfieldvalidator--is used to check whether content is entered in the validation control, and if not, an error message is generated.
2. comparevalidator--is used to enter information to compare with existing information, and if the result is false, an error is generated.
3. rangevalidator--is used to check the range of input information.
4. regularexpressionvalidator--is used to check whether the input conforms to a regular expression.
5. customvalidator--is used for developer custom validation controls.
6. validationsummary--is used to collect and display page validation results.