max marks validation

i have some problem in javascript validation..开发者_运维百科. My requirement is user sholud enter value in text box less than 5 he sholud not allow to enter value which is more than 5 he can enter 4.25 3.10 he should not enter 5.1 how to restrict user not to do this.. what is code for this.on which event we sholud call it

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you can use onBlur event of textbox and then use

if(parseFloat(yourValue)<=limit)

Also you can use isNaN(yourValue) to check if it is a number.