公司有人要，写了一个，放上来，有要得copy去用吧，下面是第一种option的value和text是一个值得方式，下面再贴不同值得方式。

运行代码框
<form method="post" name="myform"> <select name="classid" onchange="select()"></select> <select name="suid"></select> <select name="gid"></select> </form> <script language="javascript"> <!-- var arrText = new Array(5); var arrValue = new Array(arrText.length); function objSetOption(select1, select2, select3) { this.select1 = select1; this.select2 = select2; this.select3 = select3; } arrText[0]= new objSetOption("选择1:", "选择2_1:,选择2_2:", "选择3_1:,选择3_2:"); arrText[1] = new objSetOption("论文:1", "语文:1,数学:2,英语:3", "初中:2,高中:3"); arrText[2] = new objSetOption("例题:2", "显示b2_1:值b2_1,显示b2_2:值b2_2", "显示b3_1:值b3_1,显示b3_2:值b3_2"); arrText[3] = new objSetOption("显示c:值c", "显示c2_1:值c2_1,显示c2_2:值c2_2", "显示c3_1:值c3_1,显示c3_2:值c3_2"); arrText[4] = new objSetOption("显示d:值d", "显示d2_1:值d2_1,显示d2_2:值d2_2", "显示d3_1:值d3_1,显示d3_2:值d3_2"); arrText[5] = new objSetOption("显示e:值e", "显示e2_1:值e2_1,显示e2_2:值e2_2", "显示e3_1:值e3_1,显示e3_2:值e3_2"); function select(sValue1, sValue2, sValue3) { var eltSelect1 = document.myform.classid; var eltSelect2 = document.myform.suid; var eltSelect3 = document.myform.gid; var arrSelect1, arrSelect2, arrSelect3; var arrData1, arrData2, arrData3; with(eltSelect1) { var strSelect = options[selectedIndex].value; } for(i = 0;i < arrText.length;i ++) { arrSelect1 = arrText[i].select1; arrData1 = arrSelect1.split(":"); if (arrData1[1] == strSelect) { arrSelect2 = (arrText[i].select2).split(","); for(j = 0;j < arrSelect2.length;j++) { arrData2 = arrSelect2[j].split(":"); with(eltSelect2) { length = arrSelect2.length; options[j].text = arrData2[0]; options[j].value = arrData2[1]; if (arrData2[1] == sValue2) { options[j].selected = true; } } } arrSelect3 = (arrText[i].select3).split(","); for(j = 0;j < arrSelect3.length;j++) { arrData3 = arrSelect3[j].split(":"); with(eltSelect3) { length = arrSelect3.length; options[j].text = arrData3[0]; options[j].value = arrData3[1]; if (arrData3[1] == sValue3) { options[j].selected = true; } } } break; } } } function init(sValue1, sValue2, sValue3) { var eltSelect1 = document.myform.classid; var eltSelect2 = document.myform.suid; var eltSelect3 = document.myform.gid; var arrSelect1, arrSelect2, arrSelect3; var arrData1, arrData2, arrData3; if (eltSelect1 != undefined && eltSelect2 != undefined && eltSelect3 != undefined) { with(eltSelect2) { arrSelect2 = (arrText[0].select2).split(","); length = arrSelect2.length; for(i = 0;i < length;i ++) { arrData2 = arrSelect2[i].split(":"); options[i].text = arrData2[0]; options[i].value = arrData2[1]; } } with(eltSelect3) { arrSelect3 = (arrText[0].select3).split(","); length = arrSelect3.length; for(i = 0;i < length;i ++) { arrData3 = arrSelect3[i].split(":"); options[i].text = arrData3[0]; options[i].value = arrData3[1]; } } with(eltSelect1) { length = arrText.length; for(i = 0;i < arrText.length;i ++) { arrSelect1 = arrText[i].select1; arrData1 = arrSelect1.split(":"); options[i].text = arrData1[0]; options[i].value = arrData1[1]; if (arrData1[1] == sValue1) { options[i].selected = true; select("", sValue2, sValue3); } } } } } //init(); //默认初始化 init("2", "值b2_1", "值b3_2"); //更改后默认初始化 // --> </script>
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