在iOS UIWebView上运行javascript函数

Question

I am trying to run a javascript from a UIWebView. The javascript function I want to run is the one below

function SelectAnimal() {
var sel = document.getElementById('Animals');
var val = document.getElementById('AnimalToFind').value;
for(var i = 0, j = sel.options.length; i < j; ++i) {
    if(sel.options[i].innerHTML === val) {
       sel.selectedIndex = i;
       break;
    }
}

}

I know you can execute javascript in UIWebView using

(NSString *)stringByEvaluatingJavaScriptFromString:(NSString *)script

So i form the javascript string as

NSString *str = @"function SelectAnimal() {\
    var sel = document.getElementById('Animals');\
    var val = document.getElementById('AnimalToFind').value;\
    for(var i = 0, j = sel.options.length; i < j; ++i) {\
        if(sel.options[i].innerHTML === val) {\
            sel.selectedIndex = i;\
            break;\
        }\
    }\
}";

and run the javascript as

[webView stringByEvaluatingJavaScriptFromString:str];

But this doesnt seem to work. Is there something i'm doing wrong?

Answer 1

Looks like your javascript is only defining the function, but never calling it.

Try changing to:

NSString *str = @"function SelectAnimal() {\
    var sel = document.getElementById('Animals');\
    var val = document.getElementById('AnimalToFind').value;\
    for(var i = 0, j = sel.options.length; i < j; ++i) {\
        if(sel.options[i].innerHTML === val) {\
            sel.selectedIndex = i;\
            break;\
        }\
    }\
}\
selectAnimal();";