Regular Expression input box verification

Explanation

. 1 the onkeyup "= button trigger lifted," onafterpaste "= trigger after the paste, means for limiting the overall
 2  
. 3 \ D: Similar [^ 0-9 ] non-numeric
 . 4 / G: Global
 . 5  the this .Value = the this . value.replace (/ \ D / G, '' ): the numbers of all non-empty replaced
 . 6  
. 7  IMG is a schematic for an optional parameter
 . 8  I ignore case
 . 9  m multiline mode
 10  G global schema
 . 11  
12 is \ D is equivalent to [^ 0-9 ]
 13 is \ W is equivalent to [A-Za-Z ~ 0-9 ]
 14 \ W is equivalent to [^ A-Za-Z ~ 0-9 ]
 15  
16 ? match length equivalent to {0 , 1 }
 17 * match length equivalent to {0 ,}
 18+ Is equivalent to the length of the match. 1 { ,}
 . 19 \ D equivalent to [0-9]

html:

. 1  <! DOCTYPE HTML > 
2  < HTML lang = "EN" > 
. 3  < head > 
. 4      < Meta charset = "UTF-. 8" > 
. 5      < title > the Title </ title > 
. 6  </ head > 
. 7  < body > 
. 8  
. 9 can only enter a positive integer (a decimal point can not be entered): < iNPUT type = "text" placeholder = "enter numbers only" the onkeyup = "this.value this.value.replace = (/ \ D / G,'')"
10                          onafterpaste = "this.value = this.value.replace (/ \ D / G, '')" > < br > 
. 11 only letters: < INPUT type = "text" placeholder = "only letters" the onkeyup = "value.replace value = (/ [A-Za-Z ^] / IG, '')" > < br > 
12 is only input Chinese characters: < iNPUT type = "text" placeholder = "Chinese character input only" the onkeyup = "value.replace value = (/ [^ [\ u4e00- \ u9fa5] * / IG, '')" > < br > 
13 is  
14 only numbers and letters (not enter symbolic): <input type="text" placeholder= "Enter only numbers and letters" the onkeyup = "value = value.replace (/ [^ A-Za-Z0-9] / IG, '')" > < br > 
15 can only enter numbers and characters: < INPUT type = "text" placeholder = "only enter numbers and characters" the onkeyup = "value = value.replace (/ [^ 0-9 \ u4e00- \ u9fa5] / G, '')" > < br > 
16 only enter letters and characters: < iNPUT type = "text" placeholder = "only letters and characters" the onkeyup = "value = value.replace (/ [A-Za-Z ^ \ u4e00- \ u9fa5] / G, '' ) " > < br >
. 17  
18 is only input nonzero positive integer: < INPUT type = "text"placeholder = "Enter only nonzero positive integer" 
. 19                    the onkeyup = "IF (this.value.length ==. 1) = {this.value this.value.replace (/ [^ 1-9] / G, '' )} {this.value = this.value.replace the else (/ \ D / G, '')} " > < br > 
20 is  </ body > 
21 is  < Script > 
22 is      // only input is greater than or equal to zero or decimal 
23 is      function IsIntegerOrDecimal (ID) {
 24          var STR = document.getElementById (ID) .value.trim ();
 25          IF (str.length ! =  0 ) {
 26 is              var REG =  /^[1-9]\d*(\.[0-9]+)?|0(\.[0-9]+)?$/;
27             if (!reg.test(str)) {
28                 return false;
29             } else {
30                 return true;
31             }
32         }
33     }
34 </script>
35 </html>

Regular Expression input box verification

Guess you like