javascript - 检测页面中的所有iframe是否都有src

Question

我有一个包含动态数量的 iframe 的页面。 window.print() 必须在 iframe 加载后调用(即具有 src)。

如何在不迂腐的情况下用纯 JavaScript 优雅地处理这个问题？

Answer 1

function getLoadedFrames () {

    var frames = document.getElementsByTagName( 'iframe' ), // Get all iframes
        loadedFrames = [], i;

    for ( i = 0; i < frames.length; i++ ) {
        /*
            If iframe has a src attribute, that attribute has a value AND
            that value is not equal to the current window location (leaving src
            blank seems to return the current location instead of empty string)
            then add the frame to the loadedFrames array.
        */
        if ( frames[ i ].src && frames[ i ].src.length > 0 && frames[ i ].src !== window.location.href ) {
            loadedFrames.push( frames[ i ] );
        }
    }

    return loadedFrames; // An array of your 'loaded' frames
}