Javascript操作selectコントロール大全書(出所:オンライン抜粋)

Javascript   select    （  、  、  、  、  、     ）
Posted on 2007-08-08 14:56       (6036)   (16)            : JavaScript
 1  select        Value="paraValue" Item 
 2 select        Item 
 3 select        Item 
 4  select      
 5  select    value="paraValue" text "paraText" 
 6  select text="paraText"    Item    
 7  select value="paraValue" Item    
 8  select       value 
 9  select       text 
10  select       Index 
11  select   

js   
// 1.  select        Value="paraValue" Item        
function jsSelectIsExitItem(objSelect, objItemValue) {        
    var isExit = false;        
    for (var i = 0; i < objSelect.options.length; i++) {        
        if (objSelect.options[i].value == objItemValue) {        
            isExit = true;        
            break;        
        }        
    }        
    return isExit;        
}         

// 2. select        Item        
function jsAddItemToSelect(objSelect, objItemText, objItemValue) {        
    //              
    if (jsSelectIsExitItem(objSelect, objItemValue)) {        
        alert(" Item Value     ");        
    } else {        
        var varItem = new Option(objItemText, objItemValue);      
        objSelect.options.add(varItem);     
        alert("    ");     
    }        
}        

// 3. select        Item        
function jsRemoveItemFromSelect(objSelect, objItemValue) {        
    //              
    if (jsSelectIsExitItem(objSelect, objItemValue)) {        
        for (var i = 0; i < objSelect.options.length; i++) {        
            if (objSelect.options[i].value == objItemValue) {        
                objSelect.options.remove(i);        
                break;        
            }        
        }        
        alert("    ");        
    } else {        
        alert(" select       ");        
    }        
}    


// 4.  select         
function jsRemoveSelectedItemFromSelect(objSelect) {        
    var length = objSelect.options.length - 1;    
    for(var i = length; i >= 0; i--){    
        if(objSelect[i].selected == true){    
            objSelect.options[i] = null;    
        }    
    }    
}      

// 5.  select    value="paraValue" text "paraText"        
function jsUpdateItemToSelect(objSelect, objItemText, objItemValue) {        
    //              
    if (jsSelectIsExitItem(objSelect, objItemValue)) {        
        for (var i = 0; i < objSelect.options.length; i++) {        
            if (objSelect.options[i].value == objItemValue) {        
                objSelect.options[i].text = objItemText;        
                break;        
            }        
        }        
        alert("    ");        
    } else {        
        alert(" select       ");        
    }        
}        

// 6.  select text="paraText"    Item           
function jsSelectItemByValue(objSelect, objItemText) {            
    //              
    var isExit = false;        
    for (var i = 0; i < objSelect.options.length; i++) {        
        if (objSelect.options[i].text == objItemText) {        
            objSelect.options[i].selected = true;        
            isExit = true;        
            break;        
        }        
    }              
    //Show           
    if (isExit) {        
        alert("    ");        
    } else {        
        alert(" select       ");        
    }        
}        

// 7.  select value="paraValue" Item       
document.all.objSelect.value = objItemValue;    

// 8.  select       value    
var currSelectValue = document.all.objSelect.value;    

// 9.  select       text    
var currSelectText = document.all.objSelect.options[document.all.objSelect.selectedIndex].text;    

// 10.  select       Index    
var currSelectIndex = document.all.objSelect.selectedIndex;    

// 11.  select      
document.all.objSelect.options.length = 0;