页面加载时的 Javascript 字数不是 keyup

Question

I have a little bit of javascript that counts the amount of words on a box. The javascript looks like this:

<script type="text/javascript">
    function cnt(w,x){
        var y=w.value;
        var r = 0;
        a=y.replace(/\s/g,' ');
        a=a.split(' ');

        for (z=0; z<a.length; z++) {if (a[z].length > 0) r++;}
        x.value=r;
        if (r > 60) {
            x.value='Please reduce the word count'; 
        }
    } 
</script>

and the form like this:

<label>Free brochure from entry:</label>
<textarea name="freebrochureentryform" id="freebrochureentryform" onKeyUp="cnt(this,document.brochure.c)"><?php echo $row['freebrochureentryform']; ?></textarea>

<label>Brocure Entry Word Count:</label>
<input type="text" name="c" value="0" size="20" onKeyUp="cnt(document.brochure.freebrochureentryform,this)" />

Basically the bottom input field shows the amount of words in the upper one. But it only does so when you click on the upper box "freebrochureentryform", but i want it to load the amount of words as soon as the page loads not when you click the box. I guess it is to do with

onKeyUp="cnt(document.brochure.freebrochureentryform,this)" 

But have no idea what to change it to.

(Btw way Brochure is the name of my form.)

Any help greatly appreciated.

Ian

Answer 1

You can call the cnt() function on window.onload event.

And instead of listening to onkeyup event, you can listen to the more appropriate oninput (or onpropertychange for IE) event:

JSFiddle

<label>Free brochure from entry:</label>
<textarea name="freebrochureentryform" id="freebrochureentryform">Lorem Text</textarea>
<br />
<label>Brocure Entry Word Count:</label>
<input type="text" name="c" id="c" value="0" size="20" />

window.onload=function(){
    function cnt(area,output){
        var txt=area.value.replace(/^\s+|\s+$/g,"").replace(/\s+/g," ").split(" ");
        if(txt.length>10){
            output.value="Please delete some word";
        }else{
            output.value=txt.length;
        }
    }
    var textarea=document.getElementById("freebrochureentryform");
    var info=document.getElementById("c");
    if("addEventListener" in window){
        if("oninput" in textarea){
            textarea.addEventListener("input",function(){
                cnt(textarea,info);
            },false);
        }else if("onpropertychange" in textarea){
            textarea.addEventListener("propertychange",function(e){
                if((e||event).propertyName=="value"){
                    cnt(textarea,info);
                }
            },false);
        }else{
            textarea.addEventListener("change",function(){
                cnt(textarea,info);
            },false);
        }
    }else{
        textarea.attachEvent("onpropertychange",function(){
            if(event.propertyName=="value"){
                cnt(textarea,info);
            }
        });
    }
    cnt(textarea,info);
};

Some instruction:

• var txt=area.value
  • .replace(/^\\s+|\\s+$/g,"") means to trim ;
  • .replace(/\\s+/g," ") combines series of white spaces (including line feeds) into one (to better split without the need to iterate the splitted array);
  • .split(" ") split by white space (as you have already done).
• oninput is introduced in IE9 but has some buggy behavior , so you may want to try onproperychange first;
• putting function cnt() and textarea / info in window.onload makes them "safe" inside the closure . They can't pollute the global namespace, and things in global namespace can not pollute them.

Answer 2

onKeyUp triggers only on User Interaction.

If you load the side there is no Event KeyUp

so instead. Trigger it manually.

call cnt(document.brochure.freebrochureentryform,document.brochure.c) on your body manually (or onload )

Answer 3

尝试在 body onload event上调用cnt(w,x)

Answer 4

function countWords(str) {
  let arr = str.split(' ');
  let count = 0;
  if(arr.length > 0){
    for (let i = 0; i< arr.length - 1; i++){
        let sentence = arr[0];
        let bool = true;
        for(let j = 0; j < sentence.length - 1; j++){
            let charcode = arr[i].charCodeAt(j);
            if((charcode > 64 && charcode < 91) || (charcode > 96 && charcode < 123)){
            bool = false;
            }
        }
        if(bool == true){
        count += 1;
        }
    }
  }
  return arr.length - count;
}

//function calling
countWords("he is a good programer, he won 865 competitions, but sometimes he dont. 
what do you think? all test-cases should pass. done-done?");