Equivalent of jQuery's 'not' selector

问题:

Working in D3.js, I'd like to select all the elements that match a selector except for the current element.

The reason is that I'd like to mouseover a circle, and have all the other circles with the same class turn light blue, but the current circle to stay the same shade.

This is what I have currently:

vis.selectAll('circle.prospect')
.on("mouseover", function(d) { 
     console.log(d);
    d3.selectAll('circle.prospect').transition().style('opacity','0.5');
    d3.select(this).attr('opacity','1.0');
  });

In jQuery, I could do this using not. Anyone know the D3.js equivalent?

回答1:

An even simpler way to approach this would be using the power of D3's operators:

vis.selectAll('circle.prospect').on("mouseover", function(d) {
    var circleUnderMouse = this;
    d3.selectAll('circle.prospect').transition().style('opacity',function () {
        return (this === circleUnderMouse) ? 1.0 : 0.5;
    });
});

There's one difference here in that, unlike your original code, the circleUnderMouse element's opacity will be smoothly animated as well. If it's already fully opaque then probably not a big deal, otherwise you could use the .duration() operator in a similar fashion to speed the circleUnderMouse time to 0 and the others longer.

回答2:

If your elements have an unique CSS-accessible identifiers, you can use the :not() selector. Some potential examples:

d3.selectAll("circle.prospect:not(#" + this.id + ")");
d3.selectAll("circle.prospect:not(." + someUniqueClassFrom(d) + ")");
d3.selectAll("circle.prospect:not([uniqueAttr=" + this.getAttribute('uniqueAttr') + "])");

The reason d3.selectAll('circle.prospect:not(this)') doesn't work is because it's just literally saying to filter out any <this></this> elements — which is obviously not your intent, and since it's already selecting only <circle></circle> elements would have no effect regardless.

Even if you don't generally apply some unique DOM attribute, there's no reason you couldn't set one temporarily:

vis.selectAll('circle.prospect')
.on("mouseover", function(d) {
    this.id = 'temp-' + Math.random();
    d3.selectAll('circle.prospect:not(#' + this.id + ')').transition().style('opacity','0.5');
    d3.select(this).attr('opacity','1.0');
    this.id = '';
  });

That said, however, if your elements don't already have an ID assigned already, I think Ian Roberts' solution is probably what I would do instead of this temporary identifier hack.

回答3:

You can filter a selection:

vis.selectAll('circle.prospect')
.on("mouseover", function(d) { 
     console.log(d);
    var circleUnderMouse = this;
    d3.selectAll('circle.prospect').filter(function(d,i) {
      return (this !== circleUnderMouse);
    }).transition().style('opacity','0.5');
    d3.select(this).attr('opacity','1.0');
  });